Palladium catalyzed carbonylations of allyl phosphates and allyl acetates give β,γ-unsaturated esters efficiently. The latter reaction requires bromide ion as a co-catalyst.
Nickel-Catalyzed C–H Coupling with Allyl Phosphates: A Site-Selective Synthetic Route to Linear Allylarenes
作者:Xuefeng Cong、Yuexuan Li、Yu Wei、Xiaoming Zeng
DOI:10.1021/ol501707z
日期:2014.8.1
reported that a nickel/phosphine catalyst allows the C–H allylation to occur effectively with the allyl site selectivity predominantly governed by steric effects. This reaction provides a facile and predictable route for the selective preparation of linear allylarenes from readily available benzamides and allyl phosphates.
Borylative allyl–allylcoupling using allenes, bis(pinacolato)diboron, and allyl phosphates has been developed in the presence of a copper catalyst bearing an N‐heterocyclic carbene ligand. The reaction affords boryl‐substituted 1,5‐diene derivatives in good to high yields with high regioselectivity and Z selectivity.
Copper‐Catalyzed B(dan)‐Installing Allylic Borylation of Allylic Phosphates
作者:Hiroto Yoshida、Yuya Murashige、Itaru Osaka
DOI:10.1002/adsc.201900342
日期:2019.5.14
γ‐Selective B(dan)‐installing allylic borylation was found to proceed efficaciously by the reaction of an unsymmetrical diboron, (pin)B−B(dan), with allylic phosphates under copper catalysis. The resulting allyl−B(dan) was convertible into 1,3‐, 1,2‐, or 1,1‐diborylalkanes with different boron‐Lewis acidity by B(pin)‐installing hydroboration, and its C(sp3)−B(dan) bond turned out to be preferentially
Palladium-catalyzed alkoxycarbonylation of allyl phosphates under CO (1 atm) at 50-degrees-C proceeds highly efficiently to give the corresponding beta,gamma-unsaturated esters. The carbonylation of geranyl phosphate ((E)-11) under CO (1 atm) at 50-degrees-C gave ethyl ester of homogeranic acid ((E)-12) stereoselectively. The carbonylation takes place at the least substituted allylic positions with inversion of configuration. Typically, the methoxycarbonylation of cis-5-(methoxycarbonyl)-2-cyclohexen-1-yl phosphate (cis-16) gave trans-dimethyl 2-cyclohexene-1,5-dicarboxylate (trans-17) selectively. Alkoxycarbonylation of allyl acetates is performed for the first time in the presence of a catalytic amount of bromide ion. The reaction can be rationalized by assuming the mechanism which involves oxidative addition of palladium(0) species to allyl acetates to give pi-allylpalladium acetate, fast ligand exchange of the acetate with bromide, insertion of carbon monoxide to give acylpalladium species, and alkoxylation.