Stereoselective synthesis of styrene oxides via a Mitsunobu cyclodehydration.
[reaction: see text] The Mitsunobu cyclodehydration of chiral phenethane-1,2-diols (4), readily accessed from the styrene derivative (5), has been demonstrated to provide the corresponding styrene oxides (2) with high levels of stereoretention (up to 99%). Optimized reaction conditions are described, from which the combination of tricyclohexylphosphine (Chx(3)P) and diisopropylazodicarboxylate (DIAD) in THF and R = EWG provides the best results.
Weissman
S A
SA
Department of Process Research, Merck & Co., Inc, Rahway, NJ 07065, USA. steven_weissman@merck.com
Rossen
K
K
Reider
P J
PJ
D003500:Cyclization; D004852:Epoxy Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D007202:Indicators and Reagents; D064729:Neurokinin-1 Receptor Antagonists; D010720:Phosphines / Q000737:chemistry; D013373:Substance P / Q000037:antagonists & inhibitors
D004852:Epoxy Compounds; D007202:Indicators and Reagents; D064729:Neurokinin-1 Receptor Antagonists; D010720:Phosphines; D013373:Substance P; C013690:styrene oxide