95998-96-2Relevant academic research and scientific papers
Construction of the stemodane nucleus by a hydroxyl-directed intramolecular ene reaction. Total synthesis of (±)-2-desoxystemodinone
White, James D.,Somers, Todd C.
, p. 9912 - 9920 (2007/10/02)
A synthesis of the diterpene 2-desoxystemodinone was completed from the known tricyclic ketone 9 in eight steps and 35% overall yield. The key step involved a thermal intramolecular ene reaction of α-hydroxy aldehyde 21 which led to 24 in 94% yield. By contrast, a Lewis acid-catalyzed ene reaction of 21 gave oxetane 25 as the major product. The pivotal role of the hydroxyl substituent of 21 in facilitating the ene reaction was demonstrated and is rationalized by a hydrogen bond which orients the carbonyl in a favorable conformation for rearrangement.
Lewis Acid and Photochemically Mediated Cyclization of Olefinic β-Keto Esters
White, James D.,Skeean, Richard W.,Trammell, Gary L.
, p. 1939 - 1948 (2007/10/02)
Olefinic β-keto esters 8, 17, and 20, prepared by either carbomethoxylation of the parent ketone or alkylation of the dianion of methyl acetoacetate with the allylic bromide, underwent cyclization with stannic chloride in dichloromethane to give mono- and
