Premium
Stereochemistry of 1,2‐Oxaphospholanes, VIII. Synthesis, Stereochemistry, and Ring Opening Reactions of Diastereomeric 3‐Hydroxy‐2‐methoxy‐5‐methyl‐1,2‐oxaphospholan‐2‐ones
Author(s) -
Wróblewski Andrzej E.
Publication year - 1986
Publication title -
liebigs annalen der chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 0170-2041
DOI - 10.1002/jlac.198619860816
Subject(s) - chemistry , diastereomer , ring (chemistry) , substituent , triethylamine , stereochemistry , asymmetric induction , intramolecular force , transesterification , phosphonate , organic chemistry , methanol , enantioselective synthesis , catalysis
Addition of dimethyl phosphonate to acetaldol gives a 3 : 7 mixture of diastereomeric dimethyl (1,3‐dihydroxybutyl)phosphonates 3 and 4 . The relative configurations at C‐1 and C‐3 in these diols were established by the 13 C NMR data of their O ‐benzylidene derivatives. Axial preference‐for the dimethoxyphosphoryl substituent at C‐4 of the 1,3‐dioxane ring is observed. A model of the 1,3‐asymmetric induction for the Abramov reaction is proposed. Intramolecular transesterification of the phosphonates 3 and 4 in the presence of equimolar amounts of triethylamine affords diastereomeric 3‐hydroxy‐2‐methoxy‐5‐methyl‐1,2‐oxaphospholan‐2‐ones. 1,2‐Oxaphospholane ring opening reactions of the title compounds were studied by 31 P NMR.