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Double Phosphinoboration of CO₂ : A Facile Route to Diphospha-Ureas.

ABSTRACT: The reactions of CO₂ with a series of phosphinoboranes, including R₂ PBpin (R=Ph, tBu; pin=pinacol), R₂ PBMes₂ (R=Ph, tBu; Mes=2,4,6-Me₃ -C₆ H₂ ), and R₂ PBcat (R=Ph, tBu, Mes; cat=catechol) are described. Although R₂ PBpin and R₂ PBMes₂ afford products of the form R₂ PCO₂ Bpin (R=Ph 1, tBu 4) and R₂ PCO₂ BMes₂ (R=Ph 2, tBu 3), respectively, R₂ PBcat lead to further reaction affording the diphospha-ureas, (R₂ P)₂ CO (R=Ph 5, tBu 6, Mes 7), together with O(Bcat)₂ . Computational studies provide insight into the mechanism, revealing an intermediate derived from double phosphinoboration of CO₂ .

SUBMITTER: LaFortune JHW

PROVIDER: S-EPMC6916295 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Double Phosphinoboration of CO2 : A Facile Route to Diphospha-Ureas.

LaFortune James H W JHW Qu Zheng-Wang ZW Bamford Karlee L KL Trofimova Alina A Westcott Stephen A SA Stephan Douglas W DW

Chemistry (Weinheim an der Bergstrasse, Germany) 20190823 52

The reactions of CO2 with a series of phosphinoboranes, including R2 PBpin (R=Ph, tBu; pin=pinacol), R2 PBMes2 (R=Ph, tBu; Mes=2,4,6-Me3 -C6 H2 ), and R2 PBcat (R=Ph, tBu, Mes; cat=catechol) are described. Although R2 PBpin and R2 PBMes2 afford products of the form R2 PCO2 Bpin (R=Ph 1, tBu 4) and R2 PCO2 BMes2 (R=Ph 2, tB ...[more]

PMID: 31355971

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