Synthetic Photochemistry. XIII. Chiroptical Retention for the Reported "antara-antara"-3,3-Sigmatropy of Bicyclohepta-3,6-dien-2-ones

Article abstract of DOI:10.1246/bcsj.53.1006

Troponoids were shown to form 2:1-complexes with β-cyclodextrin and 1:1 complexes with α-cyclodextrin.The photoisomerization of complexed tropolone and 2-methoxytropone gave optically active 1-hydroxy- and 1-methoxybicyclo<3.2.0>hepta-3.6-dien-2-ones in improved yields.The pyrolysis of the (+)-1-methoxybicyclo<3.2.0>hepta-3,6-dien-2-one gave the (+)-3-methoxybicyclo<3.2.0>hepta-3,6-dien-2-one, ruling out the two-fold supra-antara-1,3-sigmatropy.