Premium
Highly Selective Synthesis of [( Z )‐3‐Chloro‐2‐(phenylselanyl)‐1‐alkenyl]phosphonates and 2‐Ethoxy‐4‐(phenylselanyl)‐2,5‐dihydro‐1,2‐oxaphosphole 2‐Oxides by Electrophilic Reaction of 1,2‐Alkadienylphosphonates with PhSeCl
Author(s) -
He Guangke,
Yu Yihua,
Fu Chunling,
Ma Shengming
Publication year - 2010
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.200900913
Subject(s) - chemistry , stereoselectivity , alkoxy group , nucleophile , electrophile , medicinal chemistry , stereochemistry , organic chemistry , catalysis , alkyl
The reactions of monosubstituted 1,2‐alkadienylphosphonates with PhSeCl in THF or dioxane/H 2 O (10:1) at 70 °C afforded the selenochlorination products [( Z )‐3‐chloro‐2‐(phenylselanyl)‐1‐alkenyl]phosphonates with very high chemo‐ and stereoselectivity, whereas the same reaction with di‐ and trisubstituted allenylphosphonates afforded 2‐ethoxy‐4‐(phenylselanyl)‐2,5‐dihydro‐1,2‐oxaphosphole 2‐oxides exclusively. It was interesting to note that the stereoselctivity for the selenochlorination reaction is opposite to that of the iodo‐ and selenohydroxylation reactions of (allenyl)diphenylphosphane oxides with Cl – acting as the nucleophile. The stereoselectivity of the cyclization reaction is clearly different from that of the selenochlorination reaction.