A multi-pronged mechanistic study of the phosphine-mediated conjugate addition of an alcohol to an acetylenic esterElectronic supplementary information (ESI) available. See DOI: 10.1039/c4nj01070a

• Main Authors: Stoddard, Rhonda L, Luo, Jingwei, van der Wal, Nicole, O'Rourke, Natasha F, Wulff, Jeremy E, McIndoe, J. Scott
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c4nj01070a

The conjugate addition of an alcohol to a butynoate ester using an organophosphine catalyst was monitored using pressurized sample infusion electrospray ionization mass spectrometry (PSI-ESI-MS), together with 31 P and 1 H NMR spectroscopy. The combination of methods allowed examination of the reaction progress from the perspective of reactants and products ( 1 H NMR) and insights into behaviors of the reaction intermediates and formation of byproducts ( 31 P NMR and MS). The resulting traces could be closely approximated through numerical modeling by appropriate selection of rate constants, and a sound understanding of the mechanism and the means by which oligomeric byproducts are formed allows a rational approach to experimental design. The conjugate addition of an alcohol to a butynoate ester using an organophosphine catalyst was monitored using pressurized sample infusion electrospray ionization mass spectrometry (PSI-ESI-MS), together with 31 P and 1 H NMR spectroscopy.