Generation, some synthetic uses, and 1,2-vinyl rearrangements of secondary and tertiary homoallyllithiums, including ring contractions and a ring expansion. Remarkable acceleration of the rearrangement by an oxyanionic group
作者:Boguslaw Mudryk、Theodore Cohen
DOI:10.1021/ja00063a001
日期:1993.5
addition of thiophenol to a conjugated enal or enone followed by a Wittig or Peterson olefination, (2) the reaction of a silyl enol ether with a diphenyl dithioacetal catalyzed by stannic chloride, followed by a Peterson olefination, or (3) the treatment of the lithioderivatives of phenyl thioethers or thioacetals or the corresponding cuprates with allyl halides
Regio- and Enantioselective Intermolecular Hydroacylation: Substrate-Directed Addition of Salicylaldehydes to Homoallylic Sulfides
作者:Matthew M. Coulter、Kevin G. M. Kou、Baye Galligan、Vy M. Dong
DOI:10.1021/ja107198e
日期:2010.11.24
enantioselective intermolecular olefin hydroacylation under mild conditions. Hydroacylations between homoallylic sulfides, containing a substrate-bound directing group, and salicylaldehyde derivatives occur in the presence of a spiro-phosphoramidite ligand, (R)-SIPHOS-PE, to give α-branched ketones in >20:1 selectivity and up to 97% ee. Our conditions are also applicable to the asymmetricintermolecular hydroacylation
[1,4] Phenylthio shifts of 2,4,4-trisphenylthiobutanols
作者:María-Jesús Villa、Stuart Warren
DOI:10.1016/s0040-4039(01)93509-9
日期:1989.1
The title compounds (1) undergo a [1,4]-PhS shift to give an E,Z mixture of vinyl sulphides (2) with thionyl chloride but only the Z isomer if toluene-p-sulphonic acid is used. The reaction occurs only if another PhS group is present β to the hydroxyl. The starting materials (1) were available via Michael addition of dithioacetal nucleophiles (3) to methylcrotonate followed by α-sulphenylation.