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Brønsted acid catalyzed intramolecular allylic substitution reaction of secondary and tertiary allylic alcohols has been developed. A variety of 2-vinylchromans were efficiently prepared in moderate to excellent yields. The given method features wide substrate scope, operational simplicity, and mild, metal-free reaction conditions. The practicability of the method was demonstrated by a gram-scale reaction and further derivations of the product. Preliminarily studies on a catalytic asymmetric reaction were also undertaken. [ABSTRACT FROM AUTHOR]

We demonstrated that the combination of a Pd(0) catalyst and a water‐soluble TPPMS ligand has high activity for the direct arylation of readily available allylic alcohols in the Tsuji–Trost type cross‐coupling. Various organoboron reagents can be applied, enabling rapid access to the corresponding arylated products with a wide range of functional group tolerance. Kinetic studies revealed a first‐order rate dependence for the allylic alcohol, boronic acid, CsF and Pd(0)/TPPMS concentrations. A Hammett study found a slightly positive ρ value of 0.79, suggesting that a partial negative charge is generated on the aromatic ring of the aryl boronate in the rate‐determining transmetalation step. Based on several control experiments, we concluded that the transmetalation employing CsF would proceed via the oxo‐palladium mechanism. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed asymmetric α‐allylation of ketones is a particularly useful tool for constructing stereocenters via C−C bond formation. However, this type of reaction often necessitated the use of activated ketones or pre‐prepared enol intermediates as substrates. In this study, we developed a nickel‐catalyzed α‐allylation of unactivated cycloketones with allylic alcohols to synthesize chiral cycloketones with an α‐quaternary carbon center. The reaction affords the products with 42–97% yields, 72–86% ee, and no additive is needed, and the only by‐product is water. [ABSTRACT FROM AUTHOR]

Catalytic enantioselective alkenylation of aldehydes with easily accessible alkenyl halides promoted by a chiral cobalt complex derived from a newly developed tridentate bisoxazolinephosphine is presented. Such processes represent an unprecedented reaction pathway for cobalt catalysis and a general approach that enable rapid construction of highly diversified enantioenriched allylic alcohols containing a 1,1‐, 1,2‐disubstituted and trisubstituted alkene as well as axial stereogenicity in up to 99 % yield and 99 : 1 er without the need of preformation of alkenyl–metal reagents. DFT calculations revealed the origin of enantioselectivity. [ABSTRACT FROM AUTHOR]

An N‐allylation of monosubstituted acyl hydrazines with allylic alcohols has been developed by using B(C6F5)3 catalysis. This protocol allows for convenient access to various synthetically useful N‐allylated hydrazine products in 48–96% yields with broad substrate scope and wide functional group compatibility. The operationally simple reaction proceeds without calling for stringent removal of air and moisture, and can be readily scaled up to gram scale. Preliminary mechanistic studies support the generation of an allylic carbon cation that is involved in the catalytic cycle, and the reaction proceeds via the in situ formation of diallyl ethers as intermediates. [ABSTRACT FROM AUTHOR]

An efficient rhodium(III)‐catalysed C−H activation of 3‐aryl‐1‐H‐indazoles with easily available vinylethylene carbonate has been reported. A series of allyl alcohol substituted 3‐aryl‐1‐H‐indazoles were obtained with broad functional groups tolerance and favourable stereoselectivity. Notably, C−H and C−O bonds were selectively activated in "one pot" manner, releasing CO2 as the sole by‐product and avoiding external oxidant. This protocol provides a powerful approach for the post stage C−H allylation of indazole‐based substrates. [ABSTRACT FROM AUTHOR]

The reaction was quenched with sat. aq NaHCO SB 3 sb and the mixture was extracted with CH SB 2 sb Cl SB 2 sb (3 × 2 mL). The reaction was quenched with sat. aq Na SB 2 sb S SB 2 sb O SB 3 sb (5 mL) and sat. aq NaHCO SB 3 sb (5 mL). The mixture was extracted with CH SB 2 sb Cl SB 2 sb (3 × 10 mL), and the combined organic layers were washed with brine, dried (anhyd Na SB 2 sb SO SB 4- sb ), filtered, and concentrated under reduced pressure. The reaction was quenched with sat. aq NaHCO SB 3 sb and the mixture was extracted with CH SB 2 sb Cl SB 2 sb (3 × 2 mL). [Extracted from the article]

A mild Pd‐catalyzed Tsuji‐Trost reaction of allylic alcohols with an amine nucleophile in water media was developed, leading to the green synthesis of the valuable allylic amines. This new method requires no chemical activators and sophisticated soluble ligands, and can be easily scaled up in gram scale and be readily extended to the gram scale synthesis of Naftifine, one of the best‐selling antifungal drugs, showing the practical value of this new method. [ABSTRACT FROM AUTHOR]

Rh(III)‐catalyzed chelation‐assisted C8‐selective C−H alkenylation and alkylation of 1,2,3,4‐tretrahydroquinolines with styrenes and allylic alcohols have been realized. The cationic Rh(III) catalytic system in combination with a catalytic amount of copper acetate uses oxygen as the terminal oxidant and catalyzes the stereoselective C8‐alkenylation of 1,2,3,4‐tetrahydroquinolines with styrenes to give the corresponding products in 56–93% yields with wide substrate scope and broad functional group compatibility. The reaction can be scaled up. Moreover, this protocol can be extended to the C8‐alkylation of 1,2,3,4‐tetrahydroquinolines with allylic alcohols, providing access to various 8‐(3‐oxoalkyl)‐1,2,3,4‐tetrahydroquinolines in 77–90% yields. The selection of N‐directing group is essential for catalysis, and the readily installable and removable N‐(2‐pyrimidyl) group proves to be optimal choice. Preliminary mechanistic studies are performed to gain insights into the reaction mechanism. [ABSTRACT FROM AUTHOR]

The allylic alcohol structural motif is prevalent in many important molecules and valuable building blocks. The rearrangement reaction is one of the most important transformations, however there are only a few reports for the 1,3‐rearrangement of allylic alcohols. Herein, a 1,3‐rearrangement of allylic alcohols catalyzed by an Ir(III) dihydride complex is described. This reaction could provide the corresponding less accessible allylic alcohols regio‐ and stereoselectively from readily available E/Z mixtures of the substrates. Furthermore, a tandem alkene isomerization followed by 1,3‐rearrangement of homoallylic alcohols was also realized. In addition, this rearrangement reaction could be used to synthesize the natural product Navenone B. Mechanistic investigation indicated that the reaction pathway involved a π‐allyl‐Ir(V) intermediate and that the dihydride in the iridium catalyst acts as a hydrogen switch to modulate the valence of the iridium center. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hybrid porous organic polymer containing phosphine and phosphite functionalities within its framework was synthesized. • A stable heterogeneous single-atom Rh catalyst was developed for hydroformylation of allylic alcohols. • The single-atom Rh catalyst exhibited high activity, excellent regioselectivity, and strong stability. • Mechanistic studies reveal the significant influence of the hydroxyl group in allylic alcohols on activity and regioselectivity. The regioselective hydroformylation of functionalized alkenes using heterogeneous catalysts remains a challenge. In this work, we developed a reusable heterogeneous single-atom Rh catalyst for the hydroformylation of allylic alcohols. A hybrid porous organic polymer, incorporating phosphine and phosphite functionalities within its framework, was synthesized as a support and a solid ligand to anchor and stabilize Rh sites by forming Rh-P bonds. The structure of single-atom Rh catalyst was comprehensively characterized. The resulting single-atom Rh catalyst exhibited high activity and excellent regioselectivity for the linear regioselective hydroformylation of allyl alcohol, yielding an important intermediate 4-hydroxyl butyraldehyde for 1,4-butanediol production. Furthermore, this single-atom Rh catalyst showed good stability, which could be easily separated for successive reuses several times without a significant decay in both activity and regioselectivity. Remarkably, various allylic alcohols underwent efficient and regioselective hydroformylation to their corresponding diols in good to high yields. Mechanistic studies highlighted the significant influence of the hydroxyl group in allylic alcohols on catalytic activity and regioselectivity. This work represents a significant advance in the regioselective hydroformylation of functionalized alkenes over a heterogeneous catalyst. [ABSTRACT FROM AUTHOR]

We describe cooperative bimetallic catalysis that enables regio‐/stereodivergent asymmetric α‐allylations of aldimine esters. By employing Et3B as the key activator, racemic allylic alcohols can be directly ionized to form Pd or Ir‐π‐allyl species in the presence of achiral Pd or chiral Ir complexes, respectively. The less or more substituted allylic termini of the metal‐π‐allyl species are amenable to nucleophilic attack by the chiral Cu‐azomethine ylide, the formation of which is simultaneously facilitated by Et3B, affording α‐quaternary α‐amino acids with high regioselectivity and excellent stereoselectivity. The use of readily available allylic alcohols as electrophilic precursors represents an improvement from an environmental and atom/step economy perspective. Computational mechanistic studies reveal the crucial role of the Et3B additive and the origins of stereo‐ and regioselectivities by analyzing steric effects, dispersion interactions, and frontier orbital population. [ABSTRACT FROM AUTHOR]

A simple and transition-metal-free HFIP-induced allylation reaction of tertiary allylic alcohols with thiols or sulfonyl hydrazine derivatives was reported for the efficient and highly selective synthesis of allylic sulfides and allylic sulfones. Herein, HFIP played a vital role in not only activating the allylic alcohol, but also stabilizing the allylic cation intermediate to accelerate the subsequent transformations. [ABSTRACT FROM AUTHOR]

[Display omitted] • First highly diastereoselective cascade intermolecular oxa-Michael/Michael cycloaddition. • One-pot synthesis of tetrahydropyrans from readily accessing starting materials. • Convenient and atom-economical approach for accessing tetrahydropyrans. • Synthesis of eleven novel tetrahydropyrans derivatives with three stereogenic centers. • Expansion of the synthetic applicability and versatility of the oxa-Michael reactions. An intermolecular highly diastereoselective oxa-Michael/Michael type stepwise cycloaddition was developed to synthesize tetrahydropyrans, using an allylic alcohol obtained from Baylis-Hillman reaction and methyl 2-(4-nitrophenyl) acrylate. These molecules were obtained in low to good yields using DBU as a base at 70 °C. This methodology provides a convenient and atom-economical approach for accessing tetrahydropyrans bearing three stereogenic centers, expanding the synthetic applicability and versatility of the oxa-Michael reactions. [ABSTRACT FROM AUTHOR]

Formamide as the safe cyano source! A Ni‐catalyzed cyanation of unactivated allylic alcohols and formamide to provide various α,β‐unsaturated nitriles was developed by generating the cyano unit in situ from safe and readily available formamide. [ABSTRACT FROM AUTHOR]

The asymmetric hydroalkylation of racemic allylic alcohols has been developed for the synthesis of chiral amino acid derivatives with two remote chiral centers by borrowing hydrogen catalysis. The stereoselectivities are controlled by a single chiral Ru catalyst via a dynamic kinetic asymmetric transformation process and an interesting diastereoselectivity amplification process of the product. The method could be used for the synthesis of several types of biologically important molecules, including stereodivergent synthesis of chiral pyrrolidine derivatives. [ABSTRACT FROM AUTHOR]

Several manganese‐PNP pincer catalysts for the formal hydroamination of allylic alcohols are presented. The resulting γ‐amino alcohols are selectively obtained in high yields applying Mn‐1 in a tandem process under mild conditions. [ABSTRACT FROM AUTHOR]

A direct carbonylation of allylic alcohols has been realized for the first time with high catalyst activity at low pressure of CO (10 bar). The procedure is described in detail for the carbonylation of E‐nerolidol, an important step in a new BASF‐route to (−)‐ambrox. Key to high activities in the allylic alcohol carbonylation is the finding that catalytic amounts of carboxylic anhydride activate the substrate and are constantly regenerated with carbon monoxide under the reaction conditions. The identified reaction conditions are transferrable to other substrates as well. [ABSTRACT FROM AUTHOR]

A clean method has been developed for the α‐allylation of phenyl and alpha alkyl phenyl acetonitrile with allylic alcohols. The reaction is catalyzed by nickel complexes in situ generated from a combination of Ni(cod)2 and the dppf ligand and performed at 80 °C in methanol as reaction solvent. Accordingly to this simple and base‐free protocol that only yields water as a side‐product, many allylic nitriles were synthetized with good yields. [ABSTRACT FROM AUTHOR]

A ruthenium‐catalyzed formal anti‐Markovnikov hydroamination of allylic alcohols for the synthesis of chiral γ‐amino alcohols is presented. Proceeding via an asymmetric hydrogen‐borrowing process, the catalysis allows racemic secondary allylic alcohols to react with various amines, affording enantiomerically enriched chiral γ‐amino alcohols with broad substrate scope and excellent enantioselectivities (68 examples, up to >99 % ee). [ABSTRACT FROM AUTHOR]

A in situ ring‐closing strategy was developed for the synthesis of N‐heterocyclic carbene nickel complexes. The process was carried out in air, and did not require solvent purification. The resulting nickel complexes were investigated as catalysts for the coupling of allylic alcohols with aryl boronic acids. A wide range of allylic substrates and aryl acids proved to be applicable to this catalytic system. Control experiments suggest that the Ni(0) may be the true active species in the coupling reactions. [ABSTRACT FROM AUTHOR]

The starch supported cuprous iodide nanoparticles (CuI-NPs@Starch) were synthesized in aqueous medium and characterized by transmission electron microscopy, scanning electron microscopy, X-ray powder diffraction, energy-dispersive X-ray spectroscopy and atomic absorption spectra analysis. The newly synthesized CuI NPs on starch have been demonstrated first time as an efficient catalyst for the regioselective 3-allylation reaction of N-substituted indoles as well as ring-substituted indoles using various allyl alcohols under moisture and air insensitive conditions. [ABSTRACT FROM AUTHOR]

• Isomerization of allylic alcohols. • Aqueous soluble organometallic complexes. • Homogeneous catalysis in water. • Biphasic catalysis. • Ru, Rh, Ni, Pd, Os, Ir catalysts. Isomerisation of allylic alcohols in water mediated catalytically by water soluble metal complexes is an elegant synthetic procedure for obtaining carbonyl compounds in a completely atom-economical eco-benign process with several useful applications in natural-product synthesis and in bulk chemical processes. This review is targeted to provide a general view of the goals obtained in isomerisation catalysis in water. Complexes that catalyze the isomerization of allylic alcohols in water, together with ligands and reaction conditions are compared with respect to yield, turnovers, rate and selectivity. A general overview of the mechanisms proposed for the isomerisation of allylic alcohols is also presented. Crystal structures and selected bond lengths are presented for the most representative catalytically active metal complexes. [ABSTRACT FROM AUTHOR]

A facile synthesis of tetrahydrobenzo[b]furans via gold(I)‐catalyzed cycloisomerization of 1‐aryl‐2‐propargylcyclohex‐2‐enols is described. The transformation is suggested to proceed through a gold(I)‐catalyzed tertiary allylic alcohol rearrangement to give a secondary allylic alcohol that underwent a 5‐exo‐dig addition of the hydroxyl group onto the gold(I)‐activated alkyne to give a vinylgold species. Protodeauration of the resulting vinylgold intermediate followed by aromatization furnished the tetrahydrobenzo[b]furans. [ABSTRACT FROM AUTHOR]

Two individual catalytic platforms (metal‐ and organo‐catalyzed) based on the use of an ionic liquid phase were successfully integrated for the synthesis of α‐cyano‐amine and cyanohydrin trimethylsilyl ethers from allylic alcohol. The right combination of continuous flow processes enabled access to the divergent preparation of two alternative and interesting intermediate compounds from the same starting material. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Direct trifluoromethylthiolation of allylic and propargylic alcohols. • S N 2′-type nucleophilic substitution reaction as the key step. • Broad functional group compatibility and excellent regioselectivity. • Facile synthesis of various allyl and propargyl trifluoromethyl sulfides. Abstract The reaction of easily available Morita–Baylis–Hillman (MBH) alcohols with AgSCF 3 in the presence of n -Bu 4 NI and KI affords primary allylic SCF 3 products in high yields and excellent regioselectivities. This regioselective dehydroxytrifluoromethylthiolation protocol could also be extended to propargylic alcohols for the preparation of the primary propargylic SCF 3 products. [ABSTRACT FROM AUTHOR]

A Pd(PPh3)4/acid catalyzed highly efficient and mono‐ or di‐selective allylic substitution reaction of benzothiazolylacetate and allylic alcohols has been developed. The mono‐ and di‐selectivities could be efficiently controlled by changing the reaction solvent and temperature, affording various mono‐ and di‐allylated products in good to excellent yields and selectivities. Both linear and branched allylic alcohols as well as allyl alcohol could all be well tolerated in the reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] The allylic alcohols undergo disproportionation in the presence of a catalytic amount of a rhenium complex, such as ReBr(CO) 5 , to form the corresponding alkenes and α,β-unsaturated carbonyl compounds. When allylic alcohols were treated with a secondary alcohol in the presence of the rhenium catalyst, selective reduction of the allylic alcohols proceeded to form the alkenes. [ABSTRACT FROM AUTHOR]