Photochemistry of tricyclo[5.2.2.0(2,6)]undeca-4,10-dien-8-ones: an efficient general route to substituted linear triquinanes from 2-methoxyphenols. Total synthesis of (+/-)-Delta(9(12))-capnellene.
An efficient and short entry to polyfunctionalized linear triquinanes from 2-methoxyphenols is described by utilizing the following chemistry. The Diels-Alder reactions of masked o-benzoquinones, derived from 2-methoxyphenols, with cyclopentadiene afford tricyclo[5.2.2.0(2,6)]undeca-4,10-dien-8-ones. Photochemical oxa-di-pi-methane (ODPM) rearrangements and 1,3-acyl shifts of the Diels-Alder adducts are investigated. The ODPM-rearranged products are further converted to linear triquinanes by using an O-stannyl ketyl fragmentation. Application of this efficient strategy to the total synthesis of (+/-)-Delta(9(12))-capnellene was accomplished from 2-methoxy-4-methylphenol in nine steps with 20 % overall yield.
Hsu
Day-Shin
DS
Department of Chemistry and Biochemistry, National Chung Cheng University, Minhsiung, Taiwan. chedsh@ccu.edu.tw
Chou
Yu-Yu
YY
Tung
Yen-Shih
YS
Liao
Chun-Chen
CC
D000466:Alkadienes / Q000737:chemistry*; D001952:Bridged-Ring Compounds / Q000737:chemistry*; D003408:Cresols / Q000737:chemistry*; D003500:Cyclization; D015394:Molecular Structure; D010777:Photochemistry; D012717:Sesquiterpenes / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
D000466:Alkadienes; D001952:Bridged-Ring Compounds; D003408:Cresols; D012717:Sesquiterpenes; C548741:capnellene; C025390:creosol