Stereoselective Hydrocoupling of [(1R)-exo]-3-exo-(Diphenylmethyl)bornyl Cinnamates by Electroreduction
摘要:
[GRAPHICS]The chiral auxiliary [(1R)-exo]-3-exo-(diphenylmethyl)borneol, synthesized from (1R)-(+)-camphor in three steps, was highly effective for the stereoselective hydrocoupling of its cinnamates by electroreduction. From the resulting hydrodimers, (3R,4R)-3,4-diaryladipic acid esters and (3R,4R)-3,4-diarylhexane-1,6-diols were synthesized in 87-95% ee.
Photoinduced electron transfer reaction of cyclopropanone acetals with arylmethyl methanesulfonate: generation of β-keto radical species and application to C–C bond formation
作者:Manabu Abe、Akira Oku
DOI:10.1039/c39940001673
日期:——
The photoinduced electron transfer reaction of the cyclopropanone acetals 1 with arylmethyl methanesulfonates 4 or 10 as electron acceptors was found to generate a transient pair of radicals, the β-keto radical 3 and the arylmethyl radical, which underwent a novel carbonâcarbon bond formation reaction at the sterically hindered β-position of the esters.
Cross dehydrogenative coupling of aldehydes with methanol was investigated under organocatalytic conditions based on the cooperation between N-heterocyclic carbene and eosin Y·Na as an organophotocatalyst. The combined use of eosin Y·Na and hexachloroethane (C2Cl6) was the effective method for the oxidative esterification of various aldehydes, because the oxidation steps are promoted by two pathways
[GRAPHICS]The chiral auxiliary [(1R)-exo]-3-exo-(diphenylmethyl)borneol, synthesized from (1R)-(+)-camphor in three steps, was highly effective for the stereoselective hydrocoupling of its cinnamates by electroreduction. From the resulting hydrodimers, (3R,4R)-3,4-diaryladipic acid esters and (3R,4R)-3,4-diarylhexane-1,6-diols were synthesized in 87-95% ee.