Quantum Yields of the Initiation Step and Chain Propagation Turnovers in S<sub>RN</sub>1 Reactions: Photostimulated Reaction of 1-Iodo-2-methyl-2-phenyl Propane with Carbanions in DMSO
作者:Juan E. Argüello、Alicia B. Peñéñory、Roberto A. Rossi
DOI:10.1021/jo001141m
日期:2000.10.1
Neophylradicals were generated by photoinduced electron transfer (PET) from a suitable donor to the neophyl iodide (1, 1-iodo-2-methyl-2-phenylpropane). The PET reaction of 1 with the enolate anion of cyclohexenone (2) afforded mainly the reduction products tert-butylbenzene (5) and the rearranged isobutylbenzene (6), arising from hydrogen abstraction of the neophylradical (15) and the rearranged
通过合适的供体向合适的新生物碘化物(1,1-iodo-2-methyl-2-phenylpropane)的光诱导电子转移(PET)产生新生物自由基。1与环己烯酮的烯酸酯阴离子的PET反应(2)主要产生还原产物叔丁基苯(5)和重排的异丁苯(6),这是由于新叶自由基(15)和重排的自由基16中间体的氢提取引起的, 分别。在作为自由基陷阱的二叔丁基硝基氧存在下,1与2的光刺激反应产生加合物10,收率为57%。苯乙酮(3)的烯醇阴离子与1的光诱导反应产生取代产物11(50%)和12(16%),这分别是3与自由基15和16偶合产生的。将阴离子3加入自由基15中所获得的速率常数为1。2 x 10(5)M(-)(1)s(-)(1),通过使用该基团的重排作为时钟反应。硝基甲烷(4)的阴离子在引发步骤几乎没有反应性,但是在2的存在下,在辐射下,它可产生高产率(67%)的取代产物13和仅2%的重排产物14。减
A radical decarboxylative C(sp3)–C(sp3) cross-coupling of NHPI esters and cyclopropanols was developed by combining photocatalysis and copper catalysis, which presents the efficient access to β-benzyl ketones in excellent yields. Terpyridin-4′-one used as the ligand is vital for the reaction, which could facilitate the capture of benzylic radicals by alkyl-copper species generated from copper-catalyzed