Synthesis of 1<i>H</i>-Cyclopropa[<i>b</i>]naphthalenes<i>via</i>Trapping of<i>o</i>-Benzoquinodimethanes
作者:Paul Müller、Domingo Rodriguez
DOI:10.1002/hlca.19850680423
日期:1985.6.26
1H-Cyclopropa[b]naphthalene (10a) and 3-methyl or dimethyl derivatives have been synthesized by interception of appropriately substituted o-quinodimethanes 3 with 1-bromo-2-chlorocyclopropene 5, and subsequent dehydrohalogenation of the adducts. The o-quinodimethane derivatives 3 in turn were obtained from the diynes 7via base-induced isomerization to bisallenes 8 and thermal electrocyclic ring closure
通过用1-溴-2-氯环丙烯5拦截适当取代的邻喹啉甲烷3,然后加合物脱氢卤化,合成了1 H-环丙烷[ b ]萘(10a)和3-甲基或二甲基衍生物。所述Ô -quinodimethane衍生物3依次从该二炔得到7通过碱诱导的异构化,以bisallenes 8和热电环化环合。
Sensitized photo-oxygenation of a wide variety of acyclic 1,3-dienes was investigated. The 1,4-cycloaddition of singlet oxygen to acyclic conjugated dienes was closely related to the thermal Diels-Alder reaction in stereospecificity, and steric and electronic effects of substituents. Reactivity order of singlet oxygen toward conjugated dienes and isolated C—C double bonds was exhibited as follows:
[4+2] - cycloaddition of singlet oxygen to conjugated acyclic hexadienes : evidence of singlet oxygen induced cis ⇌ trans - isomerization
作者:Klaus Gollnick、Axel Griesbeck
DOI:10.1016/s0040-4039(00)86254-1
日期:1983.1
Addition of singlet oxygen to trans, trans-2,4-hexadiene (1) occurs stereospecifically to give endoperoxide 2. With cis,trans-2,4-hexadiene (4), however, a mixture of diastereomeric endoperoxides, 2 + 5, is observed. Evidence of a singlet oxygen - induced cis ⇌ trans - isomerization is gained by competitive Diels-Alder reaction of 4 with singlet oxygen / diethyl diazenedicarboxylate.