68658-08-2Relevant academic research and scientific papers
Enantioselective phenolic a-oxidation using H2O2 via an unusual double dearomatization mechanism
McLaughlin, Michael F.,Massolo, Elisabetta,Liu, Shubin,Johnson, Jeffrey S.
, p. 2645 - 2651 (2019)
Feedstock aromatic compounds are compelling low-cost starting points from which molecular complexity can be generated rapidly via oxidative dearomatization. Oxidative dearomatizations commonly rely heavily on hypervalent iodine or heavy metals to provide the requisite thermodynamic driving force for overcoming aromatic stabilization energy. This article describes oxidative dearomatizations of 2- (hydroxymethyl)phenols via their derived bis(dichloroacetates) using hydrogen peroxide as a mild oxidant that intercepts a transient quinone methide. A stereochemical study revealed that the reaction proceeds by a new mechanism relative to other phenol dearomatizations and is complementary to extant methods that rely on hypervalent iodine. Using a new chiral phasetransfer catalyst, the first asymmetric syntheses of 1-oxaspiro[2.5]octa-5,7-dien-4-ones were reported. The synthetic utility of the derived 1-oxaspiro[2.5]octadienones products is demonstrated in a downstream complexity-generating transformation.
Enantioselective Phenolic α-Oxidation Using H2O2 via an Unusual Double Dearomatization Mechanism
McLaughlin, Michael F.,Massolo, Elisabetta,Liu, Shubin,Johnson, Jeffrey S.
supporting information, (2019/02/14)
Feedstock aromatic compounds are compelling low-cost starting points from which molecular complexity can be generated rapidly via oxidative dearomatization. Oxidative dearomatizations commonly rely heavily on hypervalent iodine or heavy metals to provide the requisite thermodynamic driving force for overcoming aromatic stabilization energy. This article describes oxidative dearomatizations of 2-(hydroxymethyl)phenols via their derived bis(dichloroacetates) using hydrogen peroxide as a mild oxidant that intercepts a transient quinone methide. A stereochemical study revealed that the reaction proceeds by a new mechanism relative to other phenol dearomatizations and is complementary to extant methods that rely on hypervalent iodine. Using a new chiral phase-transfer catalyst, the first asymmetric syntheses of 1-oxaspiro[2.5]octa-5,7-dien-4-ones were reported. The synthetic utility of the derived 1-oxaspiro[2.5]octadienones products is demonstrated in a downstream complexity-generating transformation.
Reactions of 1-Oxaspiroocta-5,7-dien-4-ones with Nucleophiles
Cacioli, Paul,Reiss, James A.
, p. 2525 - 2535 (2007/10/02)
The 1-oxaspiroocta-5,7-dien-4-ones (6-spiroepoxy-2,4-cyclohexadienones) (7) on reaction with a number of carbon, nitrogen, oxygen and halogen nucleophiles produced a variety of interesting substitution and rearrangement products (8)-(19) in moderate yields.The products derived almost exclusively from initial attack of the nucleophile with either the secondary or quaternary carbon of the epoxy ring and these various modes of reaction of the spirocyclic system are discussed.The formation of ortho-substituted phenols from the 1-oxaspiroocta-5,7-dien-4-ones suggests that the latter structures may be regarded as polarity-reversed masked phenols.Tropolones, products of a possible ring-expansion reaction, were not observed in any of the reactions investigated.
