Intermolecular reactions of electron-rich heterocycles with copper and rhodium carbenoids.

Intermolecular reactions of electron-rich heterocycles with copper and rhodium carbenoids.

Chemical Society reviews (2007-06-20)

Huw M L Davies, Simon J Hedley

ABSTRACT

This tutorial review describes the reactions of the electron-rich heterocycles pyrrole, furan, indole and benzofuran with copper and rhodium carbenoids. Two main reaction pathways are possible, involving either a concerted non-synchronous cyclopropanation or zwitterionic intermediates. A diverse range of products are possible and the outcome is very dependent on the structure of the heterocycle and the carbenoid. To emphasize this point the carbenoids are considered in terms of three classes: acceptor, acceptor-acceptor and donor-acceptor carbenoids. Unusual catalytic asymmetric transformations can be achieved with this chemistry while the asymmetric induction is strongly influenced by how the carbenoid can approach the heterocycles. This tutorial review gives an overview of the general features that govern the chemistry of metal carbenoids with heterocycles and presents a mechanistic rationale for the range of products that can be formed.

MATERIALS

Product Number

Brand

Product Description

204218

Sigma-Aldrich

Rhodium, powder, 99.95% trace metals basis

GF24911726

Rhodium, foil, not light tested, 25x25mm, thickness 0.012mm, as rolled, 99.9%

GF96356559

Rhodium, foil, light tested, 25x25mm, thickness 0.075mm, as rolled, 99.9%

GF87742659

Rhodium, foil, not light tested, 25x25mm, thickness 0.001mm, permanent polyester support, 99.85%

GF57675561

Rhodium, foil, light tested, 25x25mm, thickness 0.05mm, as rolled, 99.9%

GF22634120

Rhodium, foil, not light tested, 50x50mm, thickness 0.00075mm, permanent polyester support, 99.85%

GF80841146

Rhodium, foil, 25x25mm, thickness 0.15mm, as rolled, 99.9%

GF49946417

Rhodium, microfoil, disks, 10mm, thinness 0.50μm, specific density 620μg/cm², permanent mylar 3.5μm support, 99.99%

GF82366342

Rhodium, foil, not light tested, 50x50mm, thickness 0.00025mm, permanent polyester support, 99.9%

GF74452316

Rhodium, wire reel, 0.05m, diameter 0.5mm, as drawn, 99.9%

GF17514312

Rhodium, foil, not light tested, 25x25mm, thickness 0.00025mm, permanent polyester support, 99.9%

GF26710680

Rhodium, wire reel, 0.1m, diameter 0.12mm, as drawn, 99.9%

GF36379345

Rhodium, foil, light tested, 15x15mm, thickness 0.05mm, as rolled, 99.9%

GF64213680

Rhodium, wire reel, 0.05m, diameter 0.12mm, as drawn, 99.9%

GF81993910

Rhodium, foil, not light tested, 50x50mm, thickness 0.006mm, as rolled, 99.9%

GF15499413

Rhodium, foil, not light tested, 25x25mm, thickness 0.006mm, as rolled, 99.9%

GF14938005

Rhodium, microfoil, disks, 25mm, thinness 0.1μm, specific density 124μg/cm², permanent mylar 3.5μm support, 99.9%

GF40539405

Rhodium, foil, 25x25mm, thickness 0.1mm, as rolled, 99.9%

GF37380089

Rhodium, wire reel, 0.2m, diameter 0.25mm, hard, 99.9%

GF27499045

Rhodium, wire reel, 0.1m, diameter 0.25mm, hard, 99.9%

GF37207166

Rhodium, wire reel, 0.1m, diameter 1.0mm, as drawn, 99.9%

GF06539979

Rhodium, wire reel, 0.1m, diameter 0.5mm, as drawn, 99.9%

GF12568013

Rhodium, foil, light tested, 25x25mm, thickness 0.05mm, as rolled, x-ray quality, 99.9%

GF17496973

Rhodium, wire reel, 0.2m, diameter 0.5mm, as drawn, 99.9%

GF45819995

Rhodium, wire reel, 0.05m, diameter 0.25mm, hard, 99.9%

GF38835737

Rhodium, wire reel, 0.2m, diameter 0.12mm, as drawn, 99.9%

GF44569907

Rhodium, foil, 25x25mm, thickness 0.125mm, as rolled, 99.9%

GF35442727

Rhodium, foil, not light tested, 25x25mm, thickness 0.0005mm, permanent polyester support, 99.85%

GF04978963

Rhodium, foil, not light tested, 10x10mm, thickness 0.012mm, as rolled, 99.9%

GF71687357

Rhodium, microfoil, disks, 10mm, thinness 0.1μm, specific density 124μg/cm², permanent mylar 3.5μm support, 99.9%