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Lipases from different sources have been used for the resolution of tricarbonyl( ortho -substituted benzaldehyde oxime)chromium complexes. The effect of the nature of the solvent on enantioselectivity has been investigated.

The reaction of coumarin with the title nitrile oxide gives a single regioisomer in high yield. This result is compared with the dipolarophilic behavior of cinnamic acid esters.

Enantiomerically pure (−)-(1 R )-tricarbonyl-(2-methoxybenzaldehyde)chromium reacts with 2-mercaptobenzylalcohol to give the corresponding diastereomeric thioacetal complexes, which are separated and transformed quantitatively into the enantiomerically pure thioacetals (+)- and (−)-5 by removing the chromium tricarbonyl moiety.

The conjugate base of the pentacarbonyl(propenylpyrrolidinocarbene)chromium(0) complex reacts with aldehydes giving the corresponding aldols in good to excellent yields and in a completely γ-regioselective manner.

The reaction of (−)1R or (+)-1S-tricarbonyl(2-substituted benzaldehyde)chromium complexes with tertbutylmethanesulfonamide dianion afforded, after decomplexation and intramolecular cyclization, the enantiomerically pure N-tert-butyl-3-(2-phenyl substituted)-1,2-thiazetidine 1,1 dioxide derivatives. The hydrolytic ring opening gave the corresponding enantiopure β-aminosulfonic acid.

The antispastic drug ( R )-(−)-baclofen has been synthesized enantioselectively using a diastereoselective Michael addition reaction of the conjugate base of an enantiopure Fischer-type amino carbene to p -chloro-nitrostyrene.

The ZnCl 2 -promoted cycloaddition of a series of enantiopure ortho -substituted benzaldehyde–Cr(CO) 3 complexes and Danishefsky's diene gave the corresponding 2-aryl pyranones in good yields and complete enantiospecificity. Some of the mechanistic aspects of the cycloaddition were investigated and the reaction extended to different dienes.

The synthesis of new functionalized 1,2-bis(benzodithienyl)ethenes as well as the preparation of the new tetrathia[7]helicenes are described. The helicenes reported are new chiral push-pull molecules, with potential application in optoelectronics.

A small library of 4-(2-furyl)- or 4-(2-thienyl)-3-substituted pyrroles has been prepared by reaction of 2-(2-furyl or 2-thienyl)-1-nitro-1-alkenes (1) with secondary enamines (2). The reaction gives pyrrole derivatives by means of a Michael-type addition intermediate. Cyclization is influenced by the nature of the solvent and the substituent in the enamine β position, and by enamine-nitrogen nucleophilicity.

The coupling of diazonium salts from isatic acids with alkoxycarbonylmethylenephosphoranes leads directly to 3-oxo-indazolin-2-yl-(alkoxycarbonyl) methylenetriphenylphosphoranes, while coupling with methyl 2-chloroacetacetate gives 2-[2-(methoxycarbonyl-chloromethyliden)hydrazino] -phenyl-glyoxylic acid.

Reduction of racemic tricarbonyl(2-methoxybenzaldehyde)chromium with baker's yeast allows the ready preparation of the planar chiral alcohol and aldehyde complexes in optically active forms.