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The First Examples of Enantiomerically Pure Diphosphane Dioxides—( R P , R P )‐ and ( S P , S P )‐1,2‐Di‐ ter ‐butyl‐1,2‐diphenyldiphosphane 1,2‐Dioxides, and ( R P )‐ and ( S P )‐1‐ tert ‐Butyl‐1,2,2‐triphenyldiphosphane 1,2‐Dioxides
Author(s) -
Haynes Richard K.,
Lam William WaiLun,
Williams Ian D.,
Yeung LamLung
Publication year - 1997
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.19970031221
Subject(s) - chemistry , bromide , medicinal chemistry , reagent , nucleophilic substitution , oxygen , oxide , organic chemistry
Whereas oxidative dimerization of each of the lithiated reagents ( R P )‐ and ( S P )‐ tert ‐butylphenylphosphane oxides 1 Li and 2 Li by means of oxygen in THF at low temperature led cleanly to meso ‐1,2‐di‐ tert ‐butyl‐1,2‐diphenyldiphosphane dioxide ( 3 ), the respective nucleophilic substitution reactions of 1 Li and 2 Li with the ( R P )‐ and ( S P )‐ tert ‐butylphenylphosphinic bromides ( 4 and 6 ) in THF under argon led to the corresponding ( S P , S P )‐ and ( R P , R P )‐12‐di‐ tert ‐butyl‐1,2‐diphenyldiphosphane dioxides ( 5 and 7 ) in good yields, together with the meso ‐diphosphane dioxide 3. The structures of 3 and 5 were established by X‐ray crystallography. Similarly, the reaction of lithiated ( R P )‐phosphane oxide 1 Li with diphenylphosphinic bromide ( 8 ) or of achiral lithiated diphenylphosphane oxide 10 Li with ( R P )‐ tert ‐butylphenylphosphinic bromide ( 4 ) provided ( S P )‐ tert ‐butyltriphenyldiphosphane dioxide ( 9 ).