New C=C bond formation via nonstoichiometric titanium(IV) halide mediated vicinal difunctionalization of alpha,beta-unsaturated acyclic ketones
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Updated: Oct 16, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
1Department of Chemistry and Biochemistry, Texas Tech University, Lubbock 79409-1061, USA. qeggl@ttu.edu
Abstract:
[reaction: see text] Highly stereoselective vicinal difuctionalization of alpha,beta-unsaturated ketones for the synthesis of multifunctionalized trisubstituted alkenes is described. The new reaction employs titanium(IV) halides (0.5 equiv) as promoters and inexpensive commercial chemicals as starting materials. The reaction can be performed at room temperature in a convenient vial without the protection of inert gases. Good to excellent yields and high Z/E stereoselectivity have been realized in most cases presented (16 examples).
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