3990-93-0Relevant academic research and scientific papers
Ligandless iron-catalyzed desulfinylative C-C allylation reactions using Grignard reagents and alk-2-enesulfonyl chlorides
Volla, Chandra M. R.,Markovic, Dean,Dubbaka, Srinivas Reddy,Vogel, Pierre
experimental part, p. 6281 - 6288 (2011/02/28)
Alk-2-enesulfonyl chlorides 1-4 were synthesized by the BCl3-promoted ene reaction of alkenes with SO2. These sulfonyl chlorides were then used as electrophilic partners in iron-catalyzed desulfinylative cross-coupling reactions with different Grignard reagents (aromatic, aliphatic, and heteroaromatic). The reaction can be catalyzed with even 2 mol-% of the simple iron salt Fe(acac)3. The regioselectivity of these allylations was studied by using sulfonyl chlorides 3 and 4 with aryl Grignard reagents. The scope of these allylations was further extended by the coupling of ester-substituted alk-2-enesulfonyl chloride 10 with aromatic Grignard reagents. Symmetrical products were synthesized by double C-C allylation with the use of 2-methylidenepropane-1,3-disulfonyl chloride (12). Wiley-VCH Verlag GmbH & Co. KGaA.
Factors controlling photochemical cleavage of the energetically unfavorable Ph-Se bond of alkyl phenyl selenides
Ouchi, Akihiko,Liu, Suyou,Li, Zhong,Kumar, S. Ajaya,Suzuki, Toshiaki,Hyugano, Takeshi,Kitahara, Haruo
, p. 8700 - 8706 (2008/03/12)
(Chemical Equation Presented) Primary photochemical paths of alkyl phenyl selenides (1) were investigated, and an origin of large deviations in the chemical yields of products obtained by carbon radical reactions induced by photolysis of phenyl selenides was clarified. KrF excimer laser photolyses of n-pentyl phenyl selenide (1a) yielded 1-pentene (2a), n-pentane (3a), n-decane (4a), dipentyl selenide (5a), benzene (6), dipentyl diselenide (7a), and diphenyl diselenide (7) as major photoproducts, with compounds 2a, 3a, 4a, 5a, and 7 formed by pentyl-Se bond cleavage, and 5a, 6, and 7a by Ph-Se bond cleavage. The selectivity of the photoproducts revealed the occurrence of an unexpected amount of Ph-Se bond cleavage (35% in n-hexane at 248 nm) during photolysis. Solvent viscosity, wavelength of light, and the structure of alkyl substituents were the major factors that controlled Ph-Se bond cleavage. The ratio of Ph-Se bond cleavage decreased with increasing solvent viscosity and laser wavelength. The effect of alkyl substituents on the ratio of bond cleavages, Ph-Se/total C-Se, was investigated for five alkyl phenyl selenides; the ratio decreased in the order pentyl > 2-methylallyl > allyl > 1-ethylpropyl > tert-butyl groups. The contribution of Ph-Se bond cleavage is most probably the origin of the large deviations in the yields of radical reactions induced by photolyses of 1, which can be minimized by selecting appropriate solvents and wavelength of light.
ONE ELECTRON C-C BOND FORMING REACTIONS VIA ALLYLSTANNANES: SCOPE AND LIMITATIONS
Keck, Gary E.,Enholm, Eric J.,Yates, John B.,Wiley, Michael R.
, p. 4079 - 4094 (2007/10/02)
Free radical (or "one-electron") methodology for carbon-carbon bond forming reactions using allylstannanes is described in detail.Such reactions have the advantages of tolerating quite complex functionality in the substrate and of being nearly stoichiometric in reagents, and not requiring extensive experimentation for application to new substrates.
