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A new asymmetric synthesis of dihydrofurans and cyclopentenols has been developed and is based on the copper-catalyzed 1,2-addition of Grignard reagents to enones in combination with Sonogashira coupling/cyclization or ring-closing metathesis. By this approach, dihydrofurans with an oxygen-containing tertiary stereocenter and chiral tertiary cyclopentenols are efficiently prepared. The absolute stereochemistry of the products has been established.

The catalytic asymmetric synthesis of tertiary alcohols by the addition of organometallic reagents to ketones is of central importance in organic chemistry. The resulting quaternary stereocentres are difficult to prepare selectively by other means despite their widespread occurrence in natural products and pharmaceuticals. Here we report on a new methodology which allows access to both α-bromo-substituted and α-H-substituted allylic tertiary alcohols with excellent yields, and enantioselectivities of up to 98% using the copper(I)-catalysed 1,2-addition of Grignard reagents to enones. As an example, the methodology is applied in the synthesis of a chiral dihydrofuran.

The first catalytic enantioselective 1,2-addition of Grignard reagents (II), (V) and (VIII) to ketones (I), (IV), (VII) and (X) is reported.

A mild method for the synthesis of allylic amines by using a mixture of copper(II)perchlorate and copper metal is described.

A mild method for the conversion of vicinal dibromides to olefins by using a mixture of copper metal powder and copper(II) perchlorate and is described.

A series of new chiral palladium-bisphosphinite complexes have been prepared from readily available, naturally occurring chiral alcohols. The complexes were used to efficiently carry out catalytic allylic alkylation of 1,3-diphenylpropene-2-yl acetate with dimethyl malonate. The complexes based on derivatives of ascorbic acid carry out enantioselective alkylations, one of which showed an ee as high as 97%. Based on the structural characterization, it can be surmised that strategic placement of phenyl groups is key to higher enantioselectivities.

The insertion of an isopropoxide ligand of titanium isopropoxide into heterocumulenes gives a product that carries out metathesis at elevated temperatures by undergoing insertion of a second heterocumulene in a head to head fashion, followed by an extrusion reaction.

An efficient protocol using copper based reagents for the coupling of aryl halides with phenols to generate diaryl ethers is described. A copper(I) complex, [Cu(CH3CN)4]ClO4, or the readily available copper(II) source, CuCO3·Cu(OH)2·H2O (in combination with potassium phosphate), can be used. Aryl halides and phenols with different steric and electronic demands have been used to assess the efficiency of the procedure. The latter source of copper gives better yields under all conditions.

Allylic chlorides and acetates accelerate the reaction between copper(II) perchlorate and copper metal powder to form copper(I) perchlorate which in turn is an extremely good catalyst for the activation of these substrates towards nucleophilic substitution.