Lactone-directed intramolecular Diels-Alder cyclization: synthesis of trans-dihydroconfertifolin.
Trienes 1 and 3 were obtained in five steps from ethyl 4-acetoxy-3-oxobutanoate and 6-iodo-3-methyl-1,3-hexadiene. Intramolecular Diels-Alder cyclization of 1 and 3 gave tricyclic lactones 2 and 4 as the major products, respectively. The key intermediate 4 was converted in two steps to trans-dihydroconfertifolin (5).
Taber
Douglass F
DF
Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA. taberdf@udel.edu
Nakajima
Katsumasa
K
Xu
Ming
M
Rheingold
Arnold L
AL
D000475:Alkenes / Q000138:chemical synthesis* / Q000737:chemistry*; D000818:Animals; D003500:Cyclization; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D011161:Porifera / Q000737:chemistry*; D013237:Stereoisomerism; D013729:Terpenes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
D000475:Alkenes; D007783:Lactones; D013729:Terpenes; C469653:dihydroconfertifolin