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A series of amidocyclopropanes were prepared by direct amidocyclopropanation of alkenes, using organozinc carbenoids generated from readily available diethoxymethylamides. The amidocyclopropanation of monosubstituted alkenes led to selective formation of the trans-amidocyclopropane in most cases, but with more substituted alkenes, the stereochemical outcome of the cyclopropanation reactions was unpredictable. The amidocyclopropane products can be readily elaborated to structurally interesting cyclopropane containing amino acids or amino alcohols.

The synthesis of enantiopure aminocyclopropanes is reported, via direct aminocyclopropanation of alkenes with a zinc carbenoid containing a chiral auxiliary. The methodology was applied to the synthesis of a protected aminocyclopropane present in the immunosuppressant Belactosin A.

Chiral N-(diethoxymethyl)oxazolidinones, prepared from the corresponding oxazolidinones by heating in triethyl orthoformate can he used as organozinc carbenoid precursors for the direct enantioselective amidocyclopropanation of alkenes. The reaction is successful with it wide range of oxazolidinones and alkenes and proceeds with moderate to excellent, yield and stereoselectivity. In most cases the trans/exo amido-cyclopropane product is favoured, although certain cyclic alkenes such is indene favour the formation of the endo cyclopropane. The products can be readily elaborated to produce cyclopropylamino alcohols and amino acids. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Amidocyclopropanes are readily prepared by reaction of N-diethoxymethyl amides with alkenes in the presence of zinc amagalm, zinc chloride and chlorotrimethylsilane.

A large, laboratory-scale synthesis of a useful intermediate for coupling reactions, [4-(2-(2H)-tetrahydropyranyloxy)phenyl]boronic acid, is described.