One-pot synthesis of mixed ( )-1,2-bis(organylchalcogene)-1-alkenes precursors of the novel β-organylthio vinyllithium intermediates
摘要:
One-pot hydrochalcogenation of 1-phenylthioacetylenes using organylselenolate and organyltellurolate anions generated by the insertions of selenium and tellurium in n-organyl lithium produced (Z)-1,2-bis(organylchalcogene)-1-alkenes. The chemical reactivity of these mixed 1,2-bis(organylchalcogene)-1-alkenes was studied by Te/Li and Se/Li stereoretentive exchanges carried out with n-butyl lithium, furnishing the new intermediate species (Z)-beta-organylthio vinyllithium anions, which were trapped with aldehydes, to give the (Z)-3-hydroxy vinyl thioethers with total control of the regio- and stereochemistry. (c) 2010 Elsevier Ltd. All rights reserved.
Hydrochalcogenation of phenylthioacetylenes. Synthesis of mixed (Z)-trisubstituted 1,2-bis(organylchalcogeno)-1-alkenes
摘要:
The treatment of 1-phenylthioacetylenes with phenylselenolate and butyl or phenyltellurolate anions generated by the reaction of the corresponding dichalcogenide with NaBH4 in aqueous ethanol results in the formation of mixed 1,2-bis(organylchalcogeno)-1-alkenes of Z configuration. The phenylthio group acts as a directing and activating group for the nucleophilic addition of the chalcogenate anions (C) 2001 Elsevier Science Ltd. All rights reserved.