121239-07-4Relevant academic research and scientific papers
Palladium-Catalyzed Allyl-Allyl Reductive Coupling of Allylamines or Allylic Alcohols with H2as Sole Reductant
Zhou, Xibing,Zhang, Guoying,Huang, Renbin,Huang, Hanmin
, p. 365 - 369 (2021/01/26)
Catalytic carbon-carbon bond formation building on reductive coupling is a powerful method for the preparation of organic compounds. The identification of environmentally benign reductants is key for establishing an efficient reductive coupling reaction. Herein an efficient strategy enabling H2 as the sole reductant for the palladium-catalyzed allyl-allyl reductive coupling reaction is described. A wide range of allylamines and allylic alcohols as well as allylic ethers proceed smoothly to deliver the C-C coupling products under 1 atm of H2. Kinetic studies suggested that the dinuclear palladium species was involved in the catalytic cycle.
Photochemistry of two diphenyl β,γ-enones and a series of methyl- and phenyl-substituted α-phenyl ketones
Koppes, Margareth J. C. M.,Crabbendam, Astrid M.,Cerfontain, Hans
, p. 676 - 683 (2007/10/02)
The photochemistry of the diphenyl β,γ-enones 2 and 3 and the methyl- and phenyl-substituted α-phenyl ketones 4-9 has been studied, using mainly benzene as solvent.Irradation of 2 with λ 300 nm leads to the 1,3-acyl shift (1,3-AS) product 17, relatively small amounts of the decarbonylation products 15 and 16, and the photo-oxidation products benzophenone (18) and the α,β-unsaturated aldehyde 19.Direct irradation of the 1,3-AS product 17 yields 15, 16, 18 and 19, but no 2.Direct irradation of 3 with λ 350 nm leads mainly to the formation of 1,3-AS products (E)- and (Z)-22, the decarbonylation products (E)- and (Z)-20 and 21 and, in addition, a small amount of the cis-di-?-methane isomer 23.Direct irradation of the substituted α-phenyl ketones 4, 5, 8 and 9 with λ 300 nm leads predominantly to the formation of the radical coupling products 2,3-butanedione and 24-27, respectively, whereas 6 and 7 yield 1,2-diphenyl-1,2-ethanedione and the respective 24 and 25.The acetone-sensitized irradation of 4 leads to 4-phenyl-2-butanone (33) in addition to 2,3-butanedione and 1,2-diphenylethane (24).
Reaction of Phenyl-Substituted Allyllithiums with tert-Alkyl Bromides. Remarkable Difference in the Alkylation Regiochemistry between a Polar Process and the One Involving Single-Electron Transfer
Tanaka, Jiro,Nojima, Masatomo,Kusabayashi, Shigekazu
, p. 3391 - 3397 (2007/10/02)
The reaction of phenyl-substituted allyllithiums 1a-h with tert-alkyl bromides was investigated systematically.The alkylation regiochemistry was influenced in a complicated fashion by various factors including substituent effects, both steric and electronic, solvents, and the presence of strongly coordinating additives, tetramethylethylenediamine and hexamethylphosphoramide.On the basis of the cyclizable probe experiments, the observed regiochemistry was interpreted as follows. (a) The reaction proceeds by two alternative pathways, a polar one and single electron transfer (SET), the extent of each path being influenced by the variable factors and (b) a polar pathway favors coupling at the phenyl-substituted site (C-1), while in the case of SET the C-C bond formation occurs predominantly at the site far from the phenyl substituent (C-3).
