Enantioselective synthesis of (S)-timolol via kinetic resolution of terminal epoxides and dihydroxylation of allylamines

SV Narina, A Sudalai

Index: Narina, Srinivasarao V.; Sudalai, Arumugam Tetrahedron, 2007 , vol. 63, # 14 p. 3026 - 3030

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Citation Number: 16

Abstract

An efficient enantioselective synthesis of (S)-timolol has been described using chiral Co– salen-catalyzed kinetic resolution of less expensive (±)-epichlorohydrin with 3-hydroxy-4-(N- morpholino)-1, 2, 5-thiadiazole in good overall yield (55%) and excellent enantioselectivity (98%). Synthesis of (S)-timolol has also been achieved using hydrolytic kinetic resolution as well as asymmetric dihydroxylation routes in 90% ee and 56% ee, respectively.