38442-51-2Relevant articles and documents
Generation and EPR Spectroscopy of the First Silenyl Radicals, R2C=Si.?R: Experiment and Theory
Pinchuk, Daniel,Kratish, Yosi,Mathew, Jomon,Zborovsky, Lieby,Bravo-Zhivotovskii, Dmitry,Tumanskii, Boris,Apeloig, Yitzhak
, p. 7435 - 7439 (2019)
The first two persistent silenyl radicals (R2C=Si.?R), with a half-life (t1/2) of about 30 min, were generated and characterized by electron paramagnetic resonance (EPR) spectroscopy. The large hyperfine coupling constants (hfccs) (a(29Siα)=137.5–148.0 G) indicate that the unpaired electron has substantial s character. DFT calculations, which are in good agreement with the experimentally observed hfccs, predict a strongly bent structure (?C=Si?R=134.7–140.7°). In contrast, the analogous vinyl radical, R2C=C.?R (t1/2≈3 h), exhibits a small hfcc (a(13Cα)=26.6 G) and has a nearly linear geometry (?C=C?R=168.7°).
tert-Butylation of α,β-unsaturated nitriles by tert-butylmercury halides in the presence of iodide ion
Russell, Glen A.,Chen, Ping,Yao,Kim
, p. 5967 - 5972 (2007/10/02)
Iodide ion promotes the free radical addition of t-BuHgI to acrylonitrile to form t-BuCH2CH(CN)HgI. A facile reaction of the adduct 1-cyanoalkyl radical with t-BuHgI2- is indicated. Further promotion is observed in the pre
Electron-transfer processes. 43. Attack of alkyl radicals upon 1-alkenyl and 1-alkynyl derivatives of tin and mercury
Russell, Glen A.,Ngoviwatchai, Preecha,Tashtoush, Hasan I.
, p. 696 - 702 (2008/10/08)
Alkyl radicals, obtained by reaction of Bu3Sn? or ClHg? with alkylmercury halides, will undergo regioselective and in some cases stereospecific substitution by a free radical chain addition-elimination mechanism with 1-alkenylstannanes or -mercurials. The chain reaction is also observed for 1-alkynyl derivatives and in the photostimulated demercuration of mixed alkyl and 1-alkenyl- or 1-alkynylmercurials. Chain propagation with alkyl radical formation is also observed to occur in the reactions of β-eliminated ClHg? with Grignard reagents in PhH-THF solution. In competitive reactions of Bu3Sn? or ClHg? with pairs of alkylmercury chlorides, it is observed that a tert-butylmercurial is >1000 times more reactive than a n-butylmercurial, suggesting a concerted dissociate electron-transfer process not involving the intermediacy of RHg? species.