Calix[4]arene-fused phospholes. Issue 30 (6th July 2017)

• Record Type: Journal Article
• Authors: Elaieb, Fethi; Sémeril, David; Matt, Dominique; Pfeffer, Michel; Bouit, Pierre-Antoine; Hissler, Muriel; Gourlaouen, Christophe; Harrowfield, Jack
• Is Part Of: Dalton transactions. Volume 46:Issue 30(2017)
• Page Start: 9833
• Page End: 9845
• Publication Date: 2017-07-06
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c7dt01899a
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : A calix[4]arene-based biarylphosphine has been synthesised and catalytically converted into two diastereomeric, calixarene-fused phospholes. Abstract : An upper rim, o -(diphenylphosphinyl)phenyl-substituted calix[4]arene has been prepared and its coordinative properties investigated. When heated in the presence of palladium, the new biarylphosphine undergoes conversion into two diastereomeric, calixarene-fused phospholes. In both, the P lone pair adopts a fixed orientation with respect to the calixarene core. The more hindered phosphole (8 ), i.e. the one with the endo -oriented lone pair (cone angle 150°–175°), forms complexes having their metal centre positioned very near the calixarene unit but outside the cavity, thus inducing an unusual chemical shift of one of the methylenic ArCH2 Ar protons owing to interactions with the metal centre. As expected for dibenzophospholes, the complex [Rh(acac)(CO)·8 ], when combined with one equivalent of free8, efficiently catalyses the hydroformylation of styrene, the catalytic system displaying high regioselectivity in favour of the branched aldehyde ( b / l ratio up to 30). The optical and redox properties of the derivatives have also been investigated.