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Chiral copper complexes of 2,2′-binaphthyl-based phosphorus amidites are shown to be highly effective catalysts for the conjugate addition of dialkylzinc reagents to vinyloxiranes. The corresponding allylic alcohol reaction products (S N2′-pathway) were obtained with moderate to high regioselectivity. Both direct- (S N2-pathway) and conjugate-opening addition (S N2′-pathway) seem to proceed with complete antistereoselectivity. The enantioselectivity of these addition reactions according to a kinetic resolution protocol turned out to be high (>90% ee) with 1,3-cyclohexadiene and 1,3-cycloheptadiene monoepoxides.

A simple, efficient, stereoselective, and in some cases usefully non-regioselective method for the synthesis of β-azido alcohols by the direct opening of 1,2-epoxides with 1,1,3,3-tetramethylguanidinium azide (TMGA) in CH 3CN, catalyzed by simple transition metal-based salts [Hf(OTf) 4, Zr(OTf) 4, Yb(OTf) 3], is described. Also TMSN 3may be used in some reactions as a source of N 3−. This new method appears to be competitive with other methods previously reported.

Chiral copper complexes of BINOL- and TADDOL derived phosphorus amidites proved to be highly effective catalysts for the alkylation of alkynyl epoxides with dialkylzinc reagents. The corresponding α-allenol reaction products (S N2′-pathway) were obtained with good to excellent regio- and diastereoselectivity. The e.e. values obtained for this reaction were in the range of 26–38 %. A number of different Cu(II)-complexes were screened as possible catalysts and the results obtained indicate a complete control of the diastereoselectivity with an easy access to both enantioenriched synand anti-α-allenols.