Phenylacetonitrile, lithiated

Benzylideneacetone reacts with lithiated phenylacetonitrile under kinetic control, in THF and media that favour association, to give 1,2- and 1,4-adducts in proportions which are directly related to concentrations of monomeric and dimeric ion pair species, respectively." An attempt has been made to explain the different regioselec-tivities towards a,-unsaturated carbonyl compounds, including cyclic a-enones and cinnamaldehyde, in terms of intermediate complex formation. 

The structures of lithiated phenylacetonitrile and 1-naphthylacetonitrile have been studied in THF and HMPA-THF solution. In pure THF, Fi-NMR line width studies suggest that these species exist as contact ion pairs. In the presence of 0.25-2 equivalents of HMPA, HMPA-solvated monomeric and dimeric contact ion pairs can be identified with P and Fi-NMR spectroscopy, but with four to six equivalents of added HMPA, NMR spectra provide direct evidence for the formation of HMPA-solvated separated ion pairs. 

C-Cyanation. The reagent is obtained (70%) in two steps from benzotriazole /V-chlorination with 5% NaOCl and reaction with NaCN in MeCN, Phenylacetonitrile gives phenylmalononitrile after lithiation and exposure to 1 -cyanobenzotriazole. 

Corset J, Castella-Ventura M, Froment F, Strzalko T, Wartski L (2003) Study of the lithiated phenylacetonitrile monoanions and dianions formed according to the lithiated base used (LHMDS, LDA, or n-BuLi). 1. Evidence of heterodimer ( Quadac ) or dianion formation by vibrational spectroscopy. J Org Chem 68 3902-3911. doi 10.1021/jo020492t... 

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