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This study aims to propose a simple procedure for the development of enantioselective hydrosilylation of a ketone using catalytic amounts of [Ir(cod)2]BF4 and chiral azolium salt. Previously, catalytic asymmetric hydrosilylation reactions have used well-defined metal-N-heterocyclic carbene (NHC) complexes. The proposed method offers an important advantage of avoiding preparation of NHC-metal species. Several reaction parameters including the amount of reductant, solvent, catalyst loading and ligand structure were evaluated. In addition, the investigation of the reaction progress as a function of time revealed that an iridium species, which was generated after 5 h of reaction time, catalyzed the stereoselective reduction with almost perfect facial selection of the ketone. An attempt to obtain a catalytic active species from the reaction of [Ir(cod)2]BF4 and chiral azolium salt has been made. The newly obtained iridium species promoted the hydrosilylation of a ketone with high yield and enantioselectivity.

Objectives The clinical benefit of chemotherapy and the appropriate regimen for non-small-cell lung cancer (NSCLC) patients with interstitial lung disease (ILD) remain unclear. To fulfill this unmet medical need, we conducted a phase II study to elucidate the efficacy of S-1 in combination with carboplatin (CBDCA) in NSCLC patients with ILD. Materials and methods A total of 33 advanced or recurrent NSCLC patients with ILD were prospectively enrolled in this multicenter, open-label, phase II study. Every 4 weeks, CBDCA at a dose of AUC 5 on day 1 and S-1 at a dose of 80 mg/m2 daily for 14 days were administered. The primary endpoint was the investigator-assessed objective response rate. Results The median age at initiating chemotherapy was 70. Sixteen patients (48.5%) had squamous cell carcinoma histology. With respect to the types of ILD, the usual interstitial pneumonia pattern was dominant (66.7%). The median number of cycles administered was 3, and the overall response rate and disease control rate were 33.3% and 78.8%, respectively. The median progression-free survival, the median survival time and the 1-year survival rate were 4.8 months, 12.8 months and 51.4%, respectively. Acute exacerbation of ILD caused by chemotherapy was noted in 2 patients (6.1%). Conclusion This is the first prospective study designed to evaluate the efficacy of a specific chemotherapeutic regimen as the primary endpoint in patients with advanced NSCLC with ILD. The combination of S-1 with CBDCA may be a treatment option for advanced NSCLC patients with ILD (The clinical trial registration number: UMIN000011046).

The triple alpha reaction is one of the most important reactions in the nuclear astrophysics. However, its reaction rate in high temperature environments at T 9 > 2 was still uncertain. One of the major origins of the uncertainty was that the radiative-decay probability of the 3 1 − state in 12C was unknown. In the present work, we have determined the radiative-decay probability of the 3 1 − state to be 1.3 − 1.1 + 1.2 × 10 − 6 by measuring the 1H(12C,12Cp) reaction for the first time, and derived the triple alpha reaction rate in high temperature environments from the measured radiative-decay probability. The present result suggests that the 3 1 − state noticeably enhances the triple alpha reaction rate although the contribution from the 3 1 − state had been assumed to be small.

A 60-year-old man was admitted to our hospital with non-small cell lung cancer (NSCLC). Imaging and pathological studies revealed NSCLC, not otherwise specified (NOS), at clinical stage T3N1M0 stage IIIA. We started radiotherapy alone because of obstructive pneumonia and end-stage renal disease, but the tumors progressed rapidly and resulted in death due to air obstruction by pharyngeal metastasis. The cancer was diagnosed as pleomorphic carcinoma in an autopsy. Viable lung tumor cells, which were resistant to radiotherapy, and the pharyngeal metastasis had mesenchymal phenotypes and expressed ZEB1 but not SNAI1. These observations indicated that ZEB1-associated epithelial-mesenchymal transition has malignant features including resistance to radiotherapy and aggressive metastatic potential. ZEB1-associated EMT may be an important mechanism to understand the pathophysiology of pleomorphic carcinoma. Keywords: Pulmonary pleomorphic carcinoma, Epithelial-mesenchymal transition (EMT), ZEB1

We report three different transformations in the reaction of the hydroxyamide-functionalized azolium chloride 1 with Ag2O. These transformations were controlled by the N-substituent at the azolium ring of 1. Treatment of 1c (R = Me, alkyl) with Ag2O afforded the corresponding monodentate NHC-Ag (NHC represents N-heterocyclic carbene) complex, 6c, in 95% yield. In contrast, the reaction of 1b (R = Ph, aryl) with Ag2O yielded the corresponding 2-hydroxyoxazolidine-substituted azolium hydroxide, 7b, in 90% yield. In this transformation, perhaps the cyclization of the hydroxyamide moiety of 1b to 2-hydroxyoxazolidine occurred under the influence of the hydroxide counter anion. Several aryl-substituted azolium chlorides, 1d-f, were also converted into the corresponding cyclization products, 7d-f. However, the reaction of 1h (R = 2,4,6-Me3C6H2, aryl) with Ag2O afforded the corresponding NHC-Ag complex, 6h, in 93% yield, whereas the reaction of 1i (R = 4-MeOC6H4, aryl) with Ag2O provided a mixture of 6i and 7i in 56% and 32% yields, respectively. Moreover, the reaction of azolium chloride, 1j (R = 2,6-iPr2C6H3, aryl), which has a more sterically hindered substituent at the ortho-position of the aryl side-arm, was investigated. Treatment of 1j with Ag2O gave unexpected urea derivative, 8j, in 99% yield.

Enantioselective reduction of ketones with (EtO) 2 MeSiH catalyzed by an in-situ generated N -heterocyclic carbene (NHC) Ir complex at room temperature has been developed. A series of benzimidazolium salts were synthesized and screened in the asymmetric hydrosilylation reaction. As a result, propiophenone was efficiently reduced by the combined catalytic system of [IrCl(cod)] 2 and NHC–Ag complex derived from N -(1-naphthalenylmethyl)-substituted benzimidazolium salt L12 , affording the corresponding alcohol in 92% yield and with 92% ee. Moreover, the evaluation of an Ir catalyst precursor showed that cationic [Ir(cod) 2 ]BF 4 complex could be used. Furthermore, the introduction of a chiral hydroxyamide side arm into the benzimidazolium salt was critical for the successful design of the NHC ligand.

We have combined the low-energy neutron detector WINDS (Wide-angle Inverse-kinematics Neutron Detectors for SHARAQ) and the SAMURAI spectrometer at RIKEN Nishina Center RI Beam Factory (RIBF) in order to perform ( p , n ) reactions in inverse kinematics for unstable nuclei in the mass region around A ∼ 100 . In this setup, WINDS is used for detecting recoil neutrons and the SAMURAI spectrometer is used for tagging decay channel of heavy residue. The first experiment by using the setup was performed to study Gamow–Teller transitions from 132 Sn in April 2014. The atomic number Z and mass-to-charge ratio A / Q of the beam residues were determined from the measurements of time of flight, magnetic rigidity and energy loss. The obtained A / Q and Z resolutions were σ A / Q = 0.14 % and σ Z = 0.22 , respectively. Furthermore, owing to the large momentum acceptance ( 50 % ) of SAMURAI, the beam residues associated with the γ , 1n and 2n decay channel were measured in the same magnetic field setting. The kinematic loci of the measured recoil neutron energy and laboratory angle are clearly seen. It shows that the excitation energy up to about 20 MeV can be reconstructed.

C 2 -symmetric ester-amide functionalized azolium salt was synthesized from readily available α-amino ester such as L -serine methyl ester. The combination of a Cu salt and the chiral azolium salt promoted the asymmetric conjugate addition reaction of enones with dialkylzincs. Thus, treatment of acyclic enone such as chalcone with Et 2 Zn afforded the corresponding 1,4-adduct with up to 85% ee. An excellent ee value of 93% was obtained when 3-nonen-2-one was reacted with Et 2 Zn. The present catalytic system was found to be useful for the 1,4-addition reaction of cyclic enone. For example, the reaction of 2-cyclohepten-1-one with Et 2 Zn produced ( R )-3-ethylcycloheptanone with 80% ee.

Proton polarization at room temperature, produced in a p-terphenyl crystal by using electron population difference in a photo-excited triplet state of pentacene, was enhanced by utilizing an intense laser with an average power of 1.5 W. It was shown that keeping the sample temperature below 300 K is critically important to prevent the rise of the spin–lattice relaxation rate caused by the laser heating. It is also reported that the magnitude of proton polarization strongly depends on the time structure of the laser pulse such as its width and the time interval between them.

A series of new N-heterocyclic carbene (NHC)–Ru(II) complexes functionalized with additional hemilabile donor groups, such as a hydroxy-amide group, were successfully synthesized and structurally characterized. Preliminary studies indicated that the complexes acted as precatalysts with moderate activity in the asymmetric transfer hydrogenation at room temperature without temperature control. The investigation of the effect of varying the η 6 -arene ligands showed that these ligands appeared to significantly alter the activity of the complexes as precatalysts. Furthermore, it was revealed that the hydroxy functional group on the NHC ligand side-arm not only induced the stereoselectivity of the reaction but also enhanced the reaction rate.

The versatility of the anionic tethered NHC ligand system for the Pd-catalyzed allylic asymmetric alkylation (AAA) reaction was investigated. A well defined anionic amidate/NHC–Pd(II) complex catalyzed the AAA reaction of 1,3-diphenylprop-3-en-1-yl acetate (5) with NaCH(CO2Me)2. Similarly, the AAA reaction occurred by employing an NHC–Pd(II) complex that was generated in situ. Screening of a wide variety of NHC ligand precursors revealed that the combination of [Pd(allyl)Cl]2 and the azolium salt 9, containing a 3-pentyl group at N(3) position in the NHC ring, efficiently promoted the AAA reaction to afford the corresponding alkylated product 7 with 67% ee. Furthermore, it was found that the Pd/NHC ratio was an important factor; the AAA reaction with a Pd/NHC ratio of 1:1 took place smoothly, whereas utilization of a Pd/NHC ratio of 1:2 resulted in low conversion of the substrates probably by the formation of the catalytically inert bis(NHC)–Pd(II) complex. In fact, an independent experiment showed that the bis(NHC)–Pd(II) complex was formed by treating [Pd(allyl)Cl]2 with two equivalents of NHC–Ag complex. Further investigations on the catalytic AAA reaction revealed significant improvements in both the product yield (99%) and the enantioselectivity (81% ee) when cyclopentyl methyl ether was used as a solvent. A plausible reaction intermediate was discussed.

A new chiral N -heterocyclic carbene (NHC) ligand derived from a natural α-aminoester has been designed and synthesized. The coupling of N -methylbenzimidazole with an α-chloroacetamide derivative, which was prepared from chloroacetyl chloride and ( S )-serine methyl ester, gave the corresponding ester/amide-functionalized azolium compound 20 . The reaction of 2-cyclohexen-1-one ( 17 ) with Et 2 Zn in the presence of catalytic amounts of Cu(OTf) 2 and 20 produced ( R )-3-ethylcyclohexanone ( 18 ) as a major product. In contrast, the enantioselective conjugate addition (ECA) reaction catalyzed by Cu(OTf) 2 under the influence of a hydroxy-amide-functionalized azolium compound 15 , which was derived from ( S )- tert -leucinol, produced ( S )- 18 in preference to ( R )- 18 . A series of azolium salts were synthesized from ( S )-serine esters, and the reaction conditions for the ECA reaction were optimized to produce ( R )- 18 with 69% ee. The best results were obtained in the case of the reaction of 4,4-dimethyl-2-cyclohexen-1-one ( 34 ) with Et 2 Zn catalyzed by Cu(OTf) 2 in combination with azolium compounds. When the reaction of 34 with Et 2 Zn was carried out in the presence of catalytic amounts of Cu(OTf) 2 and 20 , ( S )-3-ethyl-4,4-dimethylcyclohexanone ( 35 ) was obtained with 97% ee, whereas the ECA reaction under the influence of hydroxy-amide-functionalized azolium 15 afforded ( R )- 35 with >99% ee. In this manner, the reversal of enantioselectivity was achieved by controlling the structure of chiral ligands.

A new monodentate iridium(III) complex bearing a readily accessible and tunable chiral hydroxy-amide functionalized N-heterocyclic carbene ligand, Cp∗Ir(NHC)Cl2, has been synthesized and characterized by crystallographic methods. The monodentate Cp∗Ir(NHC)Cl2 complex was found to act as a catalyst precursor for the stereoselective transfer hydrogenation of acetophenone in the presence of KOH even at room temperature. Moderate enantioselectivity was observed in the initial screening of the chiral ligands.

Amide-functionalized N-heterocyclic carbene (NHC) precursors such as azolium compounds have been designed and synthesized. Reaction of PdCl 2 (CH 3 CN) 2 with the NHC–Ag complex derived from the azolium salt gave [(NHC)PdCl 2 ] 2 or (NHC) 2 PdCl 2 , whereas PdCl 2 (PPh 3 ) 2 reacted with the Ag complex to afford a mixed carbene/phosphine complex such as (NHC)(PPh 3 )PdCl 2 together with a cationic [(NHC)(PPh 3 ) 2 PdCl] + Cl − whose structure was characterized by X-ray crystallographic studies. Thus, the library of NHC–Pd complexes with a tethered amide group has been successfully expanded.

A new chiral N-heterocyclic carbene (NHC) ligand was designed. Thus, an efficient synthetic route to C 2 -symmetric bis(hydroxyamide)-functionalized benzimidazolium salts from chiral β-amino alcohols was developed. The combination of Cu(OTf) 2 and the chiral azolium compound efficiently promoted the conjugate addition reaction of cyclic enone with dialkylzinc to give the corresponding adduct in good yield. Among a series of chiral NHC proligands, the functionalized benzimidazolium chloride possessing a tert -butyl group as a stereodirecting group was found to be the best choice of ligand. Under optimized reaction conditions, an excellent enantioselectivity (96% ee) was realized by allowing 2-cyclohepten-1-one to react with Bu 2 Zn at room temperature.

A simple and efficient one-pot procedure for the synthesis of α-diketones from aldehydes via benzoin condensation under the influence of a catalytic amount of azolium salt combined with DBU has been developed. Thus, aldehyde was allowed to react with the azolium salt/DBU catalytic system at room temperature, and then the reaction mixture was heated to 70 °C under air atmosphere to afford the corresponding 1,2-diketone in good yield. This would be an efficient alternative method of synthesizing α-diketones from aldehydes under metal-free conditions.

The synthesis of a series of azolium salts such as azolium iodides and chlorides having both N-anionic functional group and N-alkyl group have been developed. Reaction of azolium iodides or chlorides with Ag2O gave the corresponding NHC–Ag complexes. It was found that the resulting NHC–Ag complexes derived from azolium iodides or chlorides differ in their physical properties. The azolium chlorides as well as azolium iodides were successfully converted into the NHC–Ag complexes, which subsequently reacted with PdCl2(CH3CN)2 to give the anionic amidate/NHC–Pd complexes. Thus, a variety of the NHC–Pd complexes could be obtained from benzimidazolium and imidazolium salts.

Direct conversion of benzene to phenol was achieved by allowing it to react with a mixed gas of air and CO in the presence of HPMoV and a very small amount of 5%Pd/C in aqueous acetic acid at 150 °C for 2 h. The TON of HPMoV for the formation of phenol goes up to over 1300. The active species of the present reaction is thought to be V4+ generated from HPMoV catalyst by the reduction with CO. The role of the Pd species seems to promote the generation of V4+ from HPMoV. This method is expected to provide a direct route to phenol from benzene.

Carboxylation of benzenes with CO was successfully achieved by a combined catalytic system of Pd(OAc)2 with H5PMo10V2O40·nH2O (HPMo10V2) under the influence of O2 to form the corresponding benzoic acids in relatively high selectivity and moderate yields. The regioselectivity in the carboxylation of alkylbenzenes with CO was dominated by the steric factor rather than the electronic effect of substituents. However, the carboxylation of benzoic acid proceeded with high ortho-selectivity to give phthalic acid in preference to terephthalic acid, which shows coordination of Pd species to the carboxyl group of benzoic acid.

Measurements of deuteron–proton breakup reactions at 135 MeV/A have been made at RIKEN Accelerator Research Facility, focusing on the specific coplanar configurations. The obtained results are compared with the Faddeev calculations based on the modern nucleon–nucleon forces together with the Tucson-Melbourne99, and UrbanaIX three nucleon forces.

The 116Cd(p,n) experiment at 300 MeV has been performed for deducing the Gamow-Teller (GT) transition strengths B(GT−) in 116In. For the transition to the ground state, the B(GT−) value of 0.26 ± 0.02 is obtained. From this B(GT−) value and the B(GT+) value by a beta-decay experiment, the contribution of the intermediate ground state of 116In to the nuclear matrix element is deduced to be 0.070 ± 0.003. The B(GT−) value obtained herein is a factor of 8 less than that obtained from a previous (3He,t) measurement. This discrepancy, as well as differences in the distribution of low energy GT strength, and the width and peak energy of the GT giant resonance may be explained if the target used in the (3He,t) measurement is a Cd target with natural abundance.

Concomitant introduction of COOH and OH groups to biphenyl was achieved by allowing biphenyl to react with CO and O2 using the Pd/molybdovanadophosphoric acid catalytic system. For instance, biphenyl reacted under a mixed gas of CO (0.5 atm) and O2 (0.5 atm) in the presence of catalytic amounts of Pd(OAc)2 and H5PMo10V2O40·26H2O in acetic acid to give the corresponding hydroxybiphenylcarboxylic acids. The reaction was found to proceed through the formation of biphenylcarboxylic acid followed by hydroxylation of the resulting carboxylic acid.

Innovative carbon radical generation from hydrocarbons through a catalytic process under mild conditions has been achieved by the use of N-hydroxyphthalimide (NHPI) as a catalyst. This method can be successfully applied to a wide variety of functionalizations of hydrocarbons. Thus, alkanes are converted into alcohols, ketones, and carboxylic acids, through alkyl radicals generated by the action of NHPI. Cyclohexane was directly converted into adipic acid with O2 by NHPI combined with Mn(OAc)2. p-Xylene was oxidized to terephthalic acid in 95% yield by using an NHPI analogue as a catalyst. Alkenes could be epoxidized with H2O2 generated in situ from benzhydrol and O2 under the influence of NHPI.

The oxidation of trimethylbenzenes was examined with air or O 2 using N , N ′, N ″-trihydroxyisocyanuric acid (THICA) as a key catalyst. Thus, 1,2,3-, 1,2,4-, and 1,3,5-trimethylbenzenes under air (20 atm) in the presence of THICA (5 mol %), Co(OAc) 2 (0.5 mol %), Mn(OAc) 2 , and ZrO(OAc) 2 at 150 °C were oxidized to the corresponding benzenetricarboxylic acids in good yields (81–97%). In the aerobic oxidation of 1,2,4-trimethylbenzene by the THICA/Co(II)/Mn(II) system, remarkable acceleration was observed by adding a very small amount of ZrO(OAc) 2 to the reaction system to form 1,2,4-benzenetricarboxylic acid in excellent yield (97%). In contrast, no considerable addition effect was observed in the oxidation of 1,3,5-trimethylbenzene. This aerobic oxidation by the present catalytic system provides an economical and environmentally benign direct method to benzenetricarboxylic acids, which are very important polymer materials.

The addition of water and alcohols to non-activated terminal alkynes was found to be promoted by an iridium complex combined with Lewis acid and phosphite. Thus, terminal alkynes reacted with water or alcohols to give ketones or ketals, respectively, in good to excellent yields. α,ω-Diyne like 1,7-octadiyne was converted into 1-(2-methyl-cyclopent-1-enyl)ethanone through the intramoleculer aldol condensation of the resulting 2,7-octanedione induced by Lewis acid.

Aerobic oxidation of hydroaromatic compounds and diarylalkanes by N-hydroxyphthalimide (NHPI) under mild conditions afforded the corresponding hydroperoxides in high selectivity. Treatment of the resulting hydroperoxides with sulfuric acid followed by neutralization by a base resulted in phenol and aromatic aldehydes in high selectivity. This method provides a convenient synthetic route to aldehydes involving an aromatic moiety.

The first systematic study on the aerobic oxidation of 1,3,5-triisopropylbenzene was examined by the use of N-hydroxyphthalimide (NHPI) as a key catalyst. It was found that 1,3,5-triisopropylbenzene was efficiently oxidized with O2 in the presence of a catalytic amount of NHPI and azobisisobutyronitrile (AIBN) at 75 °C. Upon treatment of the resulting products with sulfuric acid followed by acetic anhydride led to 5-acetoxy-1,3-diisopropylbenzene and 3,5-diacetoxy-1-isopropylbenzene as major products and a small amount of 1,3,5-triacetoxybenzene. When t-butylperoxypivalate (BPP) was employed as a radical initiator, the oxidation could be achieved in good yield even at 50 °C. This oxidation provides a facile method for preparing phenol derivatives bearing an isopropyl moiety, which can be used as pharmaceutical starting materials.

A direct synthetic method of cresols from toluene by hydroxylation with air using CO as a reducing agent was developed. The reaction of toluene with air (15 atm) and CO (5 atm) in the presence of catalytic amounts of H4PMo11VO40·31H2O and Pd/C in aqueous acetic acid at 120 °C for 2 h afforded a mixture of o-, m-, and p-cresols in 9.9% yield at 83% selectivity. Cresols were obtained in 19% yield by recharging air and CO under these conditions. A variety of substituted benzenes were hydroxylated by this method to give the corresponding phenol derivatives in higher selectivity.

Synthesis of phenol and cyclohexanone in one pot was examined by means of the NHPI-catalyzed aerobic oxidation of cyclohexylbenzene. The aerobic oxidation of cyclohexylbenzene catalyzed by NHPI followed by treatment with sulfuric acid afforded phenol and cyclohexanone in good selectivities. Thus, the reaction of cyclohexylbenzene under atmospheric dioxygen (1 atm) by NHPI at 100 °C for 3 h followed by treatment with 0.3 M sulfuric acid at room temperature for 2 h resulted in phenol and cyclohexanone in 96 and 91% selectivity, respectively, at 25% conversion. This method was successfully extended to the one-pot synthesis of 4-hydroxyacetophenone and cyclohexanone.

Radical addition of aldehydes and masked aldehydes like 1,3-dioxolanes to electron-deficient alkenes was achieved by the use of catalytic amounts of BPO and N-hydroxyphthalimide (NHPI) as a polarity-reversal catalyst under mild conditions. Three-component radical coupling of 1,3-dioxolanes, maleates, and alkenes was performed in the presence of BPO and NHPI under similar conditions.

Nitrotoluenes are efficiently oxidized with air to the corresponding nitrobenzoic acids by the use of N -acetoxyphthalimide (NAPI) as a key catalyst. Thus, p - and m -nitrotoluenes under 10 atm of air in the presence of NAPI combined with Co(OAc) 2 (0.5 mol%) and Mn(OAc) 2 (0.05 mol%) at 130°C afforded p - and m -nitrobenzoic acids in 81 and 92% yields, respectively. o -Nitrotoluene was oxidized to o -nitrobenzoic acid in 51% yield by the aid of NO 2 .

Selective Wacker-type oxidation of long-chain terminal alkenes to methylketones was successfully achieved by using Pd(OAc) 2 /molybdovanadophosphate (NPMoV)/O 2 system. The selectivity of the reaction increased by slow addition of the alkenes to the catalytic solution. The oxidation of α,ω-dienes was also examined, and the selectivity of the oxidation was found to depend on the chain length of the dienes used.

The reaction of various ethers with alkenes bearing an electron-withdrawing substituent in the presence of N -hydroxyphthalimide combined with Co(OAc) 2 under dioxygen produced the corresponding adducts in which oxygen is incorporated to alkenes in good yields. Oxcetane, furan and pyrane smoothly added to ethyl fumarate even at room temperature to give coupling products in high yields. An acyclic ether like dibutyl ether also added to fumarate under mild conditions to give a hydroxylated adduct in satisfactory selectivity.

Treatment of homoallylic alcohols with NaIO 4 /NaHSO 3 reagent in aqueous t -BuOH under mild conditions produced tetrahydrofuran derivatives together with iodohydrins in a stereospecific manner. The reaction pathways of the formation of tetrahydrofurans from trans - and cis -homoallylic alcohols were found to be different. The present method provides a new approach to various alkylated tetrahydrofuran derivatives.

A new method for the synthesis of 1,3-oxazolidine derivatives has been developed. Thus, a variety of 1,3-oxazolidines was prepared by the reaction of imines with epoxides in the presence of a catalytic amount of a samarium compound such as SmI 2 , SmI 3 , or Cp* 2 Sm(thf) 2 .

Meerwein–Ponndorf–Verley-type reductive acetylation of carbonyl compounds to acetates was successfully carried out in the presence of isopropenyl acetate under the influence of a catalytic amount of Ln(O i Pr) 3 at room temperature. Various carbonyl compounds were converted into the corresponding acetates in fair to good yields.

Wacker-type oxidation of cyclopentene to cyclopentanone under dioxygen atmosphere was successfully achieved by the use of Pd(OAc) 2 and molybdovanadophosphate supported on activated carbon, [Pd(OAc) 2 –NPMoV/C], catalyst. Thus, the reaction of cyclopentene under O 2 (1 atm) in aqueous acetonitrile acidified by CH 3 SO 3 H in the presence of [Pd(OAc) 2 –NPMoV/C] at 50°C produced cyclopentanone in 85% yield along with a small amount of cyclopentenone (1%).

Various types of substituted alkylpyrroles were synthesized in regioselective manner by the cyclization of nitroalkenes with imines catalyzed by Sm(O i -Pr) 3 under mild conditions. Tetrahydroindole derivative was also synthesized in fair yield by the use of cyclic nitroalkene and imine as starting material. This method provides a novel alternative route for the regioselective synthesis of substituted alkylpyrrole derivatives.

A methodology for the aerobic oxidation of organic substrates in the absence of any metal catalyst has been established using combined catalytic system consisting of N-hydroxyphthalimide and quaternary ammonium bromide. Thus, various hydrocarbons were successfully oxidized under dioxygen atmosphere to the corresponding oxygenated compounds in good selectivities.

Aerobic oxidation of various sulfides using N-hydroxyphthalimide (NHPI) in the presence of alcohols was examined. For instance, the oxidation of diphenyl sulfide in the presence of cyclohexanol and a catalytic amount of NHPI in benzonitrile gave diphenyl sulfoxide in 88 % yield along with a small amount of diphenyl sulfone (7 %). The actual oxidant in this oxidation is considered to be an α-hydroxy hydroperoxide generated by the autoxidation of alcohol assisted by the NHPI which serves as the radical catalyst.

Aerobic oxidation of primary alcohols to aldehydes was efficiently performed using a Ru(PPh 3 ) 3 Cl 2 /hydroquinone system under atmospheric oxygen at 60 °C. A primary alcohol even in the presence of a secondary one was selectively oxidized to the corresponding aldehyde in high yield.

Radical addition of 1,3-dimethyladamantane to diethyl acetylenedicarboxylate was catalyzed by NHPI combined with Co species under O 2 to give different adducts, ethyl 2-(3,5-dimethyladamantyl)-2-oxoethanoate and a normal adduct whose ratio was found to depend on the O 2 concentration of the reaction system.

The reaction of adamantane under atmospheric nitric oxide in the presence of N-hydroxyphthalimide (NHPI) which serves as the radical catalyst in a mixed solvent of benzonitrile and acetic acid afforded 1-N-adamantylbenzamide as a principal product along with small amounts of 1-nitroadamantane and 1-hydroxyadamantane. On the other hand, 1-nitroadamantane was obtained in good yield upon treatment of adamantane with NO O 2 .

Isophorone was smoothly oxidized with molecular oxygen by molybdovanadophosphate supported on the active carbon (NPMo V/C) to give 3-formyl-5,5-dimethyl-2-cyclohexen-1-one in relatively high selectivity. The regioselectivity of the oxidation by NPMo V/C was found to be just opposite to that of the conventional oxidations. The pore size of the supports appears to be an important factor governing the regioselectivity.

Cyclotrimerization of internal and terminal alkynes was performed using a new triple catalytic system, Pd(II)/chlorohydroquinone/NPMoV, under atmospheric oxygen. Internal alkynes such as 3-hexyne and 4-octyne were converted into hexaethyl- and hexapropylbenzenes in quantitative yields. Terminal alkyne, t-butylacetylene, afforded 1,3,5-tri-t-butylbenzene without formation of unsymmetrical tri-t-butylbenzenes. The reaction did not take place in the absence of oxygen.

A new route to α-hydroxy-γ-butyrolactones through three-component radical coupling of 1,3-dioxoranes, acrylates, and molecular oxygen using N-hydroxyphthalimide (NHPI) as a key catalyst has been developed. For example, the addition of 1,3-dioxarane to methyl acrylate under dioxygen by NHPI followed by catalytic hydrogenation of the resulting adduct on Pd/C afforded α-hydroxy-γ-butyrolactone in good yield. This method provides a facile approach to α-hydroxy-γ-butyrolactones, which are difficult to synthesize by conventional methods.

Molybdovanadophosphate (NPMoV)/hydroquinone/O 2 system was found to be an efficient reoxidation system in palladium-catalyzed oxidations of alkenes and related compounds. Thus, acetoxylations of cycloalkenes utilizing molecular oxygen as the final oxidant were cleanly performed using the multicatalytic system consisting of Pd(OAc) 2 /hydroquinone/NPMoV to form 3-acetoxy-1-cycloalkenes in good yields. For example, cyclopentene and cyclohexene were converted into the corresponding allylic acetates in almost quantitative yields. Omitting hydroquinone from the catalytic system led to low yields of the acetates. Acetoxylation of cyclooctene was satisfactorily achieved by replacing hydroquinone of the multicatalytic system by chlorohydroquinone. Molybdovanadophosphates, which catalyze the smooth dehydrogenation of hydroquinone to benzoquinone with dioxygen, were found to rapidly promote the present Pd(II)-catalyzed acetoxylation of cycloalkenes. By the use of a mixed solvent of ethanol and water under these conditions, Wacker type oxidations of cyclohexene and styrene were accomplished in fair to good yields. Monosubstituted alkenes such as ethyl acrylate and acrylonitrile underwent the acetalization by the present catalytic system to give the corresponding acetals in quantitative yields.

Aldol type condensation of imines has first been achieved via a catalytic process using samarium diiodide (Sml 2 ) at room temperature to form α,β-unsaturated imines in good yields. The condensation was markedly facilitated by the presence of formates or aldehydes which promote the elimination of amines from aldol adducts. It was found that the 1:2 reaction of amines with aldehydes under the influence of Sml 2 also led to α,β-unsaturated imines in satisfactory yields.