Synthesis of functionalised cyclopentanes by intramolecular radical-mediated cyclisations of terminal allenic ketones
作者:Gerald Pattenden、Graeme M. Robertson
DOI:10.1016/s0040-4020(01)97179-0
日期:1985.1
Electrolysis of a series of terminal allenic ketones e.g. (7), (10), (17) and (21) is shown to result in intramolecular reductive cyclisation, through the -mode, producing five-membered rings, (8), (9), (20) and (22) respectively, incorporating a bridgehead hydroxyl group. The unsaturated alcohols (8), (20) and (22), are also obtained when the allenic ketones (7), (17) and (21) are treated with sodium
Synthesis of spiroisoindolinones by palladium-catalyzed heterocyclization of 2-iodobenzoyl chloride with ketimines
作者:Chan Sik Cho、Xue Wu、Li Hong Jiang、Sang Chul Shim、Hong Rak Kim
DOI:10.1002/jhet.5570360147
日期:1999.1
2-Iodobenzoyl chloride reacts with ketimines in acetonitrile at 100° undercarbonmonoxidepressure in the presence of a catalytic amount of a palladium catalyst together with triethylamine to afford the corresponding spiroisoindolinones in high yields.
The Castagnoli–Cushman reaction of bicyclic pyrrole dicarboxylic anhydrides bearing electron-withdrawing substituents
作者:Maria E. Chizhova、Dmitry V. Dar’in、Mikhail Krasavin
DOI:10.1016/j.mencom.2020.07.030
日期:2020.7
Four anhydrides of 1-(carboxymethyl)pyrrole-2-carboxylic acids bearing electron-withdrawing substituents at positions 6 or 7 of the bicyclic system have been investigated in the Castagnoli–Cushman reaction with imines. 6-Benzoyl- and 7-sulfamoyl-substituted anhydrides demonstrated lower reactivity while 7-benzoyl derivative displayed broader substrate scope. These findings have been rationalized from
Formation of 1,2,3,4-tetrahydro-2-pyridones by aza-annulation of imines with acrylate derivatives
作者:K. Paulvannan、John R. Stille
DOI:10.1021/jo00046a011
日期:1992.9
The aza-annulation of imines with activated acrylate derivatives was studied as a means of preparing the corresponding 1,2,3,4-tetrahydro-2-pyridones. Through the use of reagents known to facilitate the formation of amide bonds from carboxylic acids, several methods of activating the acrylate species were compared. The acrylate derivatives studied were acryloyl chloride and acrylic anhydride as well as acrylic acid activated by reaction with EtO2CCl, (PhO)2P(O)N3, or MCPI. Optimum annulation was obtained with imines derived from cyclohexanone to produce octahydro-2-quinolone products. The N-isobutylimine prepared from cyclopentanone also produced selective ring annulation to efficiently produce the corresponding bicyclic product, but the reaction with the imine of n-butanal produced lower yields of cyclic product. Ring formation was relatively unaffected by substituents at the a-position of the acrylate derivative, demonstrated by the use of methacrylate, but beta-substituents hindered the annulation process and, in turn, increased the amounts of byproduct resulting from only N-acylation of the imine. Increasing the steric bulk of the imine alkyl substituent produced the opposite effect; the relative amount of N-acylation compared to complete aza-annulation was diminished as the size of the substituent was increased. Mechanistic features of the reaction are discussed in terms of product distribution and competition experiments.