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The enantioselective reduction of prochiral ketones with borane in the presence of a chiral ligand has received considerable attention. Hydroxylamine-based chiral ligands with amide and hydroxyl functions in the presence of other co-ordinating groups are highly effective in these asymmetric reductions. The current work presents a simple one step synthesis of a series of β-hydroxyamide-based ligands from the reaction between 3-hydroxy-2-naphthoic acid and chiral amino alcohols and their applications as catalysts in asymmetric borane-mediated reductions of aromatic prochiral ketones in THF. The reductions provided the corresponding secondary alcohols with up to 96% ee and in good to excellent yields (89–99%). DFT calculations at B3LYP/6-31+g(d) level offered theoretical models to account for the enantioselectivity imposed by the chiral ligands in the reductions of the ketones.

This review is focused on new developments reported during the last 3 years concerning the catalytic performances of in situ formed or preformed NHC--Pd(II) complexes (NHC: $N$-heterocyclic carbene) for cross-coupling reactions such as Heck--Mizoraki (often shortened to the Heck reaction), Kumada, Negishi, Suzuki--Miyaura (often shortened to the Suzuki reaction), Sonogashira and Hiyama couplings, and the Buchwald--Hartwig aminations, which are extremely powerful in the formation of C--C and C--heteroatom bonds. Due to the great number of publications and limited space here, we made a special attempt to compile the relevant data in tables, which we hope will serve as a guide for chemists interested in these reactions. The syntheses of the precatalysts and the generally accepted reaction mechanisms are also briefly described.

New rhodium(I) and iridium(III) complexes are synthesized and used for the reduction of the keto bond of acetophenone derivatives under hydrogen transfer conditions.

Four novel C 2 -symmetric macrocyclic compounds with a pyridine function and possessing amide and ester lingeages were prepared. The enantiomeric discrimination abilities of these macrocycles against α-phenylethylammonium and α-(1-naphthyl)ethylammonium perchlorate salts were measured by standard 1 H NMR titration techniques in DMSO- d 6 . A binding constant ratio of 31 (Kbind(S)/Kbind(R)) for two enantiomers of α-(1-naphthyl)ethylammonium salt with the macrocyclic host ( S , S )- 4 bearing phenyl arms was observed, which corresponds to an enantiomeric discrimination of approximately 94%. Molecular dynamic calculations were performed for some of the supramolecular complexes to in order to gain insight into the mode of molecular recognition between the macrocyclic compounds and ammonium salts; these results were consistent with experimental observations, which may be relevant to those in biochemical processes occurring in organisms.

A synthesis of the naturally occurring xanthone toxyloxanthone B is described, in which the key step is the regioselective addition of a methyl salicylate to a substituted benzyne followed by cyclization of the intermediate aryl anion to form the xanthone, the regiochemistry of the aryne addition being confirmed by X-ray crystallography. Subsequent introduction of the pyran ring by [3,3]-rearrangement and deprotection completed the synthesis

The asymmetric Michael addition of aldehydes to nitroolefins was investigated using a combination of l -prolinamide derivatives and various acidic additives. ( S )-1,1′-Bi-2-naphthol was found to be the most effective co-catalyst and afforded the nitroaldehyde products with excellent yields (up to 95%), enantiomeric excesses (up to 99%) and diastereoselectivity ratios (up to 99:1).

A highly effective, easy to handle, and environmentally benign process for palladium-mediated Suzuki cross-coupling was developed. The in situ prepared three-component system of Pd(OAc) 2 , 1,3-dialkyltetrahydrodiazepiniumchlorides (2a-e), and K 2 CO 3 catalyzes quantitatively the Suzuki-Miyaura cross-coupling of deactivated aryl chloride.

Four functionalized bis(1,4,5,6-tetrahyropyrimidinium) salts (2a-d) have been prepared and characterized by conventional spectroscopic methods and elemental analyses. A highly effective, easy to handle and environmentallybenign process for palladium mediated Suzuki cross-coupling was developed. The in situ prepared three component system Pd(OAc) 2 / bis( 1,4,5,6-tetrahyropyrimidinium) bromides (2a-d) and Cs 2 CO 3 catalyses quantitatively the Suzuki cross-coupling of deactivated aryl chloride.

The 2- or 2,6-position(s) of aromatic aldehydes were directly and selectively arylated with aryl chlorides or bromides in the presence of a catalytic system prepared in situ from Pd(OAc)2, imidazolinium chlorides ( 1–5 ) and Cs2CO3.

The synthesis and structural properties of three novel imidates, 11,13-bis-(2-amino-ethylimino)-1,10-dioxa-4,7-dithiacyclotridecane (2), 11,13-bis-(3-aminopropylimino)-1,10-dioxa-4,7-dithiacyclotridecane, (3) and 2,11-dioxa-5,8-dithia-13,16,19,22-tetraazabicyclo[10.10.1]tricosa-1(22),12-diene, (4) have been described. These compounds were synthesized by treating 1,10-dioxa-4,7-dithiacyclotridecane-11,13-diester (1) with the appropriate diamine under N2 and their structures have been characterised by elemental analyses, 1H- and 13C-nmr, ir, and mass spectral studies. Elemental analyses and spectroscopic data support the proposed imidate structures. In addition, total energy and heat of formation (Figure 2) calculated for imidates 2a-4a and 2b-4b by the semiempirical AM1 calculations have shown that imidates 2b-4b having intramolecular hydrogen bonds are more stable (5-10 kcal/mol) than compounds 2a-4a.

A novel metal-free phthalocyanine and its nickel(II) and copper(II) phthalocyaninato complexes were prepared. The new compounds were characterized by elemental analyses, 1H- and 13C-NMR, IR, UV-Vis, and mass spectral data. The NMR and/or UV-Vis spectra of these compounds showed extremely broad bands and/or peaks. This phenomenon seems to be related to the presence of the sulfur substituents, which is consistent with the data observed for similar compounds. The absorption spectra of these compounds were greatly affected by aggregation processes.