title: Rhodium-catalyzed double [2 + 2 + 2] cycloaddition of 1,4-bis(diphenylphosphinoyl)buta-1,3-diyne with tethered diynes: a modular, highly versatile single-pot synthesis of NU-BIPHEP biaryl diphosphines.
abstract: Rhodium-catalyzed double [2 + 2 + 2] cycloaddition of 1,4-bis(diphenylphosphinoyl)buta-1,3-diyne with tethered diynes provides a straightforward, single-pot procedure for the synthesis of a new class of tropos biaryl diphosphine, NU-BIPHEP. This methodology represents a significant improvement on existing multistep procedures. Enantiopure Lewis acid platinum complexes of these diphosphines are highly efficient catalysts for carbonyl-ene and Diels-Alder reactions, and ruthenium diphosphine-diamine complexes catalyze the asymmetric reduction of ketones to give ee's that rival those obtained with their BINAP counterpart.
authors.affiliation: School of Natural Sciences, Chemistry, Newcastle University, Newcastle Upon Tyne, UK. simon.doherty@ncl.ac.uk
authors.forename: Simon
authors.initials: S
authors.lastname: Doherty
authors.forename: Julian G
authors.initials: JG
authors.lastname: Knight
authors.forename: Catherine H
authors.initials: CH
authors.lastname: Smyth
authors.forename: Ross W
authors.initials: RW
authors.lastname: Harrington
authors.forename: William
authors.initials: W
authors.lastname: Clegg