Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6448809 | Molecular Catalysis | 2017 | 5 Pages |
â¢Propargyl alcohol carbonylation is efficiently catalyzed by Drent's catalyst.â¢The selectivity towards alkyl 2-(hydroxymethyl)acrylates is >99%.â¢Turnover frequency numbers >450 hâ1 are obtained under mild conditions.â¢The mechanism of catalyst deactivation has been determined.
The challenging carbonylation of propargyl alcohol is effectively catalyzed by Pd(OAc)2 in combination with diphenyl-(6-methyl-pyridin-2-yl)phosphine and methanesulfonic acid. In dichloroethane at 20-50 °C, the reaction affords with almost complete regioselectivity alkyl 2-(hydroxymethyl)acrylates. Turnover frequency numbers (TOF) of up to 450 hâ1 can be achieved working at 50 °C, while a maximum turnover number (TON) of about 730 is obtained at 30 °C. The catalyst longevity is limited because the carbonylation product reacts with the phosphorus atom of the ligand to give a quaternary phosphonium salt. This reaction leads to deactivation of the catalyst and eventually to palladium black formation.
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