Visible-light-induced direct C-H arylation of S,S-functionalized internal alkenes, that is, α-oxo ketene dithioacetals and analogues, has been efficiently realized with aryldiazonium salts (ArNBF) as coupling partners and Ru(bpy)Cl·6HO as photosensitizer at ambient temperature. The strategy to activate the internal olefinic C-H bond by both the alkylthio and electron-withdrawing functional groups was investigated. The synthetic protocol was successfully applied to the synthesis of all-carbon tetrasubstituted alkenes including tamoxifen.

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The epoxidation of styrene catalyzed by a reaction-controlled phase transfer catalyst [(C 18 H 37 (30%)+C 16 H 33 (70%))N(CH 3 ) 3 ] 3 -[PW 4 O 16 ] with H 2 O 2 in a biphasic medium was investigated. Under certain conditions, the selectivity for styrene oxide was 95%, the conversion of styrene based on H 2 O 2 was 85%, and the reaction time was less than 1 h. During the reaction, this catalyst powder formed soluble active species by the action of H 2 O 2 , was recovered as a precipitate, and was reused after H 2 O 2 was used up. After two times recycling, the catalyst kept almost the same activity.