Fluoride-induced 1,2-elimination of o-trimethylsilylphenyl triflate provided a convenient route to benzyne under mild conditions where detriflation from an intermediary aryl anion appeared to occur in preference to protonation even in the presence of alcohols.

Fluoride-induced 1,2-elimination of o-trimethylsilylphenyl triflate to benzyne under mild conditions

The hydroboration of olefins with Et(2)BH provides diethyl(alkyl)boranes 2 which readily undergo a boron-zinc exchange with Et(2)Zn providing a range of polyfunctional primary, secondary, and benzylic diorganozincs. The resulting diorganozincs 3 have been reacted with various electrophiles (allylic halides, acid chlorides, alkylidenemalonates, ethyl propiolate, nitroolefins) in the presence of CuCN.2LiCl with excellent yields. With secondary dialkylzincs prepared from diastereomerically pure diethyl(alkyl)boranes, the boron-zinc exchange occurs with loss of stereochemistry. The asymmetric addition of 3 to aldehydes in the presence of the chiral catalyst 55 furnishes optically active polyfunctional secondary alcohols (50 to over 96% ee).

Preparation of Functionalized Dialkylzincs via a Boron-Zinc Exchange. Reactivity and Catalytic Asymmetric Addition to Aldehydes.

http://www.rsc.org/suppdata/CC/b5/b505392g/B505392G.PDF

Facile insertion reaction of arynes into carbon–carbon σ-bonds

Alkene synthesis via .beta.-functionalized organosilicon compounds

Tetrahedron report number 234 Synthetic aspects of the use of organosilicon compounds under nucleophilic catalysis conditions

beta. Elimination of unsaturated silanes. Acetylene via dechlorosilylation

Generation of 1,2-dehydrobenzene from the dehalosilylation of (o-halophenyl)trimethylsilanes

Trialkylchlorosilanes can be synthesized in high yield and excellent purity from corresponding trialkylsilanes by the use of cupric chloride in acetonitrile.

Edward M. Dexheimer

Papers

beta. Elimination of unsaturated silanes. Acetylene via dechlorosilylation

Generation of 1,2-dehydrobenzene from the dehalosilylation of (o-halophenyl)trimethylsilanes

An Improved Method for the Preparation of Trialkylchlorosilanes from Trialkylsilanes Using Cupric Chloride

Beta-eliminierung ungesaettigter silane, acetylen durch entchlorsilylierung