Phosphine-catalyzed dimerization of activated alkenes under ambient and high pressure conditions
作者:Gérard Jenner
DOI:10.1016/s0040-4039(00)00346-4
日期:2000.4
Acrylic compounds dimerizeunder Morita–Baylis–Hillman conditions in the presence of soluble phosphines. Dimerization of β-substituted analogs may require highpressures. The process is selective and high yielding and affords densely functionalized products.
The N-heterocycliccarbene (NHC)-catalyzed dimerizations of a variety of disubstituted Michael acceptors have been investigated. In addition to the tail-to-tail dimerization of methacrylates reported previously, the scope of vinylidene substrates expands to γ-methyl-α-methylene-γ-butyrolactone, dimethyl 2-methylenepentanedioate, dimethyl itaconate, methacrylamides, and 2-isopropenylbenzoxazole, none
Aluminum alkyl-tertiary amine complex was found to induce the catalytic dimerization of methyl crotonate (MCr) to dimethyl 2-methylpent-4-ene-1,3-dicarboxylate (1) and dimethyl 2-methylpent-cis-3-ene-1,3-dicarboxylate (2). The of the γ-hydrogen of the MCr molecule. Dimer 2 is formed through the isomerization of dimer 1. The complex of AlR3 with a bidentate ligand, sparteine, produces dimer 1, selectively
Saal, Wolfgang von der; Reinhardt, Robert; Seidenspinner, Hubert-Matthias, Liebigs Annalen der Chemie, 1989, p. 703 - 712
作者:Saal, Wolfgang von der、Reinhardt, Robert、Seidenspinner, Hubert-Matthias、Stawitz, Josef、Quast, Helmut
DOI:——
日期:——
Catalytic Dimerization of Crotonates
作者:James C. A. Flanagan、Eun Joo Kang、Nathaniel I. Strong、Robert M. Waymouth
DOI:10.1021/acscatal.5b00930
日期:2015.9.4
A room-temperature dimerization of crotonates into 2-ethylidene-3-methylpentanedioates provides a sustainable route to difunctional monomers for step-growth polymerizations. We report two such dimerizations: (1) an organocatalytic dimerization using the N-heterocyclic carbene 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene ((IPr2Me2)-Pr-i) and (2) a rapid dimerization (under 15 s to full conversion) using potassium t-butoxide in THF. In addition to unsaturated diesters, the resulting dimers can be easily converted to other step-growth monomers; namely, their corresponding diacids and saturated diesters.