Pedrosa Rafael, Andrés Celia, Nieto Javier, del Pozo Soledad
Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, Dr. Mergelina s/n, 47011-Valladolid, Spain.
J Org Chem. 2003 Jun 13;68(12):4923-31. doi: 10.1021/jo034251c.
[2+2] photocycloadditions involving chiral 3-acryloyl-2-vinylperhydro-1,3-benzoxazines derived from (-)-8-aminomenthol are highly diastereoselective reactions. The facial selectivity depends on the type of substitution at the vinyl double bond, and always leads to cis-fused bicyclic derivatives. The de is good for compounds with one substituent at the outer carbon of the double bond at C-2, but only one diastereomer is formed in cyclizations of compounds with two substituents at that position. The elimination of the menthol appendage gives enantiopure 3-azabicyclo[3.2.0]heptanes.
涉及源自（-）-8-氨基薄荷醇的手性3-丙烯酰基-2-乙烯基全氢-1,3-苯并恶嗪的[2 + 2]光环加成反应是高度非对映选择性反应。面选择性取决于乙烯基双键处的取代类型，并且总是生成顺式稠合的双环衍生物。对于在C-2处双键的外碳上具有一个取代基的化合物，非对映体过量良好，但在该位置具有两个取代基的化合物环化时仅形成一种非对映体。薄荷醇附属物的消除得到对映体纯的3-氮杂双环[3.2.0]庚烷。
