Enantio- and diastereo-convergent synthesis of (2R,5R)- and (2R,5S)-Pityol through enzyme-triggered ring closure
摘要:
A short chemoenzymatic synthesis of the (2R,5S)- and (2R,5R)-stereoisomer of the bark beetle pheromone Pityol 1 was achieved from (+/-)-Sulcatol 2 in an enantio- and diastereo-convergent fashion without the formation of any 'unwanted' stereoisomer. The key steps include: (i) lipase-catalyzed deracemization of (+/-)-2 using kinetic resolution coupled to an in-situ inversion or alternatively, dynamic resolution using combined lipase- and Ru-catalysis: and (ii) creation of the second stereogenic center by an epoxide hydrolase-catalyzed diastereo-convergent hydrolysis of a haloalkyl oxirane, followed by spontaneous ring Closure to form 1 in a stereoselective fashion. (C) 2001 Published by Elsevier Science Ltd.
Enantio- and diastereo-convergent synthesis of (2R,5R)- and (2R,5S)-Pityol through enzyme-triggered ring closure
摘要:
A short chemoenzymatic synthesis of the (2R,5S)- and (2R,5R)-stereoisomer of the bark beetle pheromone Pityol 1 was achieved from (+/-)-Sulcatol 2 in an enantio- and diastereo-convergent fashion without the formation of any 'unwanted' stereoisomer. The key steps include: (i) lipase-catalyzed deracemization of (+/-)-2 using kinetic resolution coupled to an in-situ inversion or alternatively, dynamic resolution using combined lipase- and Ru-catalysis: and (ii) creation of the second stereogenic center by an epoxide hydrolase-catalyzed diastereo-convergent hydrolysis of a haloalkyl oxirane, followed by spontaneous ring Closure to form 1 in a stereoselective fashion. (C) 2001 Published by Elsevier Science Ltd.