title: 2,8'-disubstituted-1,1'-binaphthyls: a new pattern in chiral ligands.
abstract: The title binaphthyls 19 and 26, which are the positional isomers of 2-methoxy-2'-(diphenylphosphino)-1,1'-binaphthyl (MOP, 19) and 2-amino-2'-hydroxy-1,1'-binaphthyl (NOBIN, 26), have been synthesized by Suzuki coupling as the key step (10 + 15-->18), followed by functional group transformations, involving C-P and C-N bond formation (18-->19 and 18-->23). Racemic intermediate 22 was resolved by co-crystallization with N-benzylcinchonidinium chloride and the absolute configuration determined by X-ray crystallography. These novel binaphthyls are configurationally stable and, as such, potentially usable as chiral ligands in asymmetric reactions. Michael addition of the glycine-derived enolate 40 to methyl acrylate, carried out in the presence of (R)-(-)-27 as the chiral phase-transfer catalyst, afforded L-glutamic acid (S)-(+)-43 of 92% ee (after hydrolysis of the primary product).
authors.affiliation: Department of Chemistry, University of Glasgow, Glasgow G12 8QQ, UK. stepanv@natur.cuni.cz
authors.forename: Stĕpán
authors.initials: S
authors.lastname: Vyskocil
authors.forename: Ludĕk
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authors.lastname: Meca
authors.forename: Iva
authors.initials: I
authors.lastname: Tislerová
authors.forename: Ivana
authors.initials: I
authors.lastname: Císarová
authors.forename: Miroslav
authors.initials: M
authors.lastname: Polásek
authors.forename: Syuzanna R
authors.initials: SR
authors.lastname: Harutyunyan
authors.forename: Yuri N
authors.initials: YN
authors.lastname: Belokon
authors.forename: Russel M J
authors.initials: RM
authors.lastname: Stead
authors.forename: Louis
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authors.lastname: Farrugia
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Lockhart
authors.forename: William L
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authors.lastname: Mitchell
authors.forename: Pavel
authors.initials: P
authors.lastname: Kocovský