Photooxygenation of 3,3-dialkylsubstituted allyl alcohols. Occurrence of syn preference in the ene addition of1O2 atE/Z-isomeric allyl alcohols
作者:Karl H. Schulte-Elte、Bernard L. Muller、Herv� Pamingle
DOI:10.1002/hlca.19790620318
日期:1979.4.20
oxygenation products formed. The rate and selectivity of the 1O2 additions were found to be markedly dependent on the degree of substitution (i.e. H-availability) at the allyl position which is Z-orientated to the carbinol group. The allyl alcohols with a Z-3-methyl group, 1 and the E-isomers of 7 to 10, showed practically the same reactivity towards 1O2 and formed only the two oxygenation products of type
3,3-二烷基对称取代的烯丙醇1-6(A,表1)和3-甲基-3-烯丙基烷基取代的醇的E和Z异构体的染料敏化光氧合(1 O 2反应)研究了7-11(A 1,表2)。α,β-环氧乙醛B和B 1以及β-氢过氧-均烯丙基醇C,C 1和D 1实际上是唯一形成的氧化产物。发现1 O 2加成的速率和选择性显着取决于Z取向于甲醇基团的烯丙基位置上的取代度(即H-可用性)。烯丙基醇与一个Ž -3-甲基,1和Ë的异构体7至10,显示出几乎朝向相同的反应性1 Ò 2和仅形成类型的两个氧化产物乙1和C ^ 1(比率接近60:40)。相反,具有Z -3-亚甲基基团2和Z-异构体为7至9的烯丙醇与1 O 2的反应更慢,并在反应中生成了所有三种可能的产物B 1,C 1和D 1。 〜80:10:10的比例大不相同。但是,从醇7到10的E-和Z异构体,总是强烈赞成两种氧化产物的形成(85-100%),这是由于1 O在双键的