72035-66-6Relevant academic research and scientific papers
Total synthesis of (+)-ar -macrocarpene
Khatua, Arindam,Niyogi, Sovan,Bisai, Vishnumaya
, p. 7140 - 7143 (2019)
This report features the first catalytic asymmetric total synthesis of a sesquiterpene, (+)-ar-macrocarpene (1), in 7 steps with 42.1% overall yields from commercially available inexpensive 5,5-dimethylcyclohexane 1,3-dione. This strategy relies on a key [3,3]-sigmatropic rearrangement effecting reductive transposition through allylic diazene rearrangement (ADR) in a single step from intermediate allylic alcohol (+)-12 under the Mitsunobu reaction conditions with o-nitrobenzenesulfonyl hydrazide (o-NBSH). Enantioselective reduction of α-bromo vinylogous ester 16 under the Corey-Bakshi-Shibata reduction conditions forges the required stereocenter in the allylic alcohol (+)-12 in a highly enantioenriched manner (95% ee).
Arynic Condensations of Ketone Enolates. 15. New Synthetic Applications of the Condensation of α,β-Unsaturated Ketone Enolates on Benzyne
Essiz, Munir,Guillaumet, Gerald,Brunet, Jean-Jacques,Caubere, Paul
, p. 240 - 246 (2007/10/02)
Arynic condensations of both cyclic and acyclic α,β-unsaturated ketone enolates are studied.First, condensation of substituted cyclohexenone enolates with benzyne leads to a new class of cyclobutanic alcohols 6.Ring opening of 6 under basic conditions is described as a good means of synthesizing benzocyclooctadienones 10 and 19, and, in appropriate cases, benzocyclooctenediones of type 12.Thermal dehydration of 6 affords 1,3-disubstituted naphthalenes in good yields.Second, condensations of a few acyclic α,β-unsaturated ketone enolates with benzyne are shown to be of synthetic usefulness; depending on the substituents on both sides of the carbonyl group, these condensations may lead either to substituted naphthalenes or to phenyl ketones or tetralones.
