Rhodium-Catalyzed Intramolecular C−H Insertion of α-Aryl-α-diazo Ketones

Direct diazo transfer proceeds smoothly with α-aryl ketones. The derived α-aryl-α-diazo ketones cyclize efficiently with Rh catalysis to give the corresponding α-aryl cyclopentanones

The Neber Route to Substituted Indoles

Two complementary procedures have been developed for the conversion of the oximes of α-aryl ketones to azirines. On heating, the azirines rearrange smoothly to the corresponding indoles. The overall transformation offers a versatile route to indoles, complementary to the Fischer indole synthesis

Synthesis of (−)-Hamigeran B

The synthesis of (−)-hamigeran B has been achieved, based on a new approach to cyclopentane construction, the rhodium-mediated intramolecular C−H insertion of α-aryl−α-diazoketones. The endo-isopropyl group was installed by selective hydrogenation of a cyclopropylidene substituent

Synthesis of the Reported Structure of <i>trans</i>-Africanan-1α-ol

A trisubstituted cyclopentane chiron has been prepared by dynamic kinetic reduction of a pulegone-derived β-keto ester. This chiron served as the starting material for the synthesis of the reported structure of the tricyclic sesquiterpene trans-africanan-1α-ol. The synthetic material was not congruent with the natural product

Synthesis of the Reported Structure of <i>trans</i>-Africanan-1α-ol

A trisubstituted cyclopentane chiron has been prepared by dynamic kinetic reduction of a pulegone-derived β-keto ester. This chiron served as the starting material for the synthesis of the reported structure of the tricyclic sesquiterpene trans-africanan-1α-ol. The synthetic material was not congruent with the natural product

Synthesis of the Reported Structure of <i>trans</i>-Africanan-1α-ol

A trisubstituted cyclopentane chiron has been prepared by dynamic kinetic reduction of a pulegone-derived β-keto ester. This chiron served as the starting material for the synthesis of the reported structure of the tricyclic sesquiterpene trans-africanan-1α-ol. The synthetic material was not congruent with the natural product

Synthesis of (+)-Coronafacic Acid

An enantioselective synthesis of (+)-coronafacic acid has been achieved. Rhodium-catalyzed cyclization of an α-diazoester provided the intermediate cyclopentanone in high enantiomeric purity. Subsequent Fe-mediated cyclocarbonylation of a derived alkenyl cyclopropane gave a bicyclic enone that then was hydrogenated and carried on to the natural product

Synthesis of the Reported Structure of <i>trans</i>-Africanan-1α-ol

A trisubstituted cyclopentane chiron has been prepared by dynamic kinetic reduction of a pulegone-derived β-keto ester. This chiron served as the starting material for the synthesis of the reported structure of the tricyclic sesquiterpene trans-africanan-1α-ol. The synthetic material was not congruent with the natural product

Cyclohexanones by Rh-Mediated Intramolecular C–H Insertion

Some long chain α-aryl α-diazo ketones under Rh catalysis cyclize efficiently to the corresponding cyclohexanones. This is in marked contrast to the cyclizations of α-diazo β-ketoesters, which consistently deliver cyclopentanone products

Synthesis of the Carboline Disaccharide Domain of Shishijimicin A

A synthetic route to the carboline disaccharide domain (2) of shishijimicin A (1) has been developed. The convergent synthesis relies on a novel application of the Reetz–Müller-Starke reaction to form the central, sulfur-bearing quaternary carbon center and addition of the carboline structural motif as a dianion to a disaccharide aldehyde fragment