Photochemical decomposition of benzocyclobutenone p-toluenesulfonylhydrazone
Photochemical decomposition of benzocyclobutenone p-toluenesulfonylhydrazone
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苯并环丁酮对甲苯磺酰腙的光化学分解
DOI：
10.1021/jo00088a037
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Zilpa Rosental
中科院分区：
文献类型：
--
作者：
A. Frimer;J. Weiss;Zilpa Rosental
苯并环丁烯酮对甲苯磺酰腙的光化学分解产生多种产物，包括1,1′-双（苯并环丁烯二烯）6a的E-和z -异构体；顺式反式苯并环丁烯三聚体7；cyclohepatrienes 8 - 10;抗-抗（11）、抗-syn（12）和syn-syn（13）构象的苯并环丁烯酮嘧啶；抗和顺苯并环丁烯酮n-苯并环丁烯基n-甲苯腙（分别为14和15）；(benzocyclobutenyl)肼(16);苯并环丁基对甲苯砜（17）；和苯并环丁烯酮1。讨论了它们的分离、鉴定和形成机理。结果表明，芳基碳烯在烯烃上的加成有利于生成阻碍较大的合成产物，而芳基碳烯5在芳基烯烃（苯乙烯和二聚体6）上的加成有利于生成阻碍较小的合成产物。此外，在这些体系中观察到的最小位阻效应可能是由于环丁基环的90°角，它将苯基环拉回，从而使其位阻贡献最小化
The photochemical decomposition of benzocyclobutenone p-toluenesulfonylhydrazone led to a wide variety of products including the E- and Z-isomers of 1,1'-bi(benzocyclobutenylidene) 6a; cis-transbenzocyclobutenylidene trimer 7; cyclohepatrienes 8-10; benzocyclobutenone azine in it's anti-anti (11), anti-syn (12), and syn-syn conformations (13); anti- and syn-benzocyclobutenone N-benzocyclobutenyl-N-tosylhydrazone (14 and 15, respectively); (benzocyclobutenyl)hydrazine (16); benzocyclobutenyl p-tolyl sulfone (17); and benzocyclobutenone 1. Their isolation, identification and mechanism of formation are discussed. The data indicate that while the addition of arylcarbenes to alkenes results in the preferential formation of the more-hindered syn products, arylcarbene 5 adds to aryl olefins (styrenes and dimer 6) in a stereospecific anti orientation to give the less-hindered product. In addition, the minimal steric effects observed in these systems presumably results from the 90° angle of the cyclobutyl ring, which pulls the phenyl ring back and thus minimizes its steric contribution