Cyclopropanation catalyzed by osmium porphyrin complexes

Journal Article · Wed Mar 24 04:00:00 EST 1993 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00059a059· OSTI ID:6215432

Smith, D A; Reynolds, D N; Woo, L K ^[1]

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1. Ames Lab., IA (United States)

The authors report herein the use of osmium porphyrins as stereoselective cyclopropanation catalysts using ethyl diazoacetate with a variety of alkenes. In addition, their studies show that an isolable carbene complex ((TTP)Os[double bond]CHCO[sub 2]Et) is capable of catalytically and stoichiometrically cyclopropanating styrene. Several significant aspects have evolved from the use of osmium meso-tetra-p-tolyporphyrin complexes as catalysts for the cyclopropanation of a variety of alkenes by ethyl diazoacetate. This system provides the highest anti/syn isomer ratio reported to date (a/s = 10) for the catalytic cyclopropanation of styrene by ethyl diazoacetate. Unlike typical cyclopropanation catalysts which produce cyclopropenes from alkyne substrates, the osmium porphyrin catalysts generate bicyclobutanes from phenylacetylene. Moreover, the authors have isolated, on preparative scale, the first carbene complex, (TTP)Os[double bond]CHCO[sub 2]Et, that is catalytically active toward cyclopropanation. The fact that this carbene complex can stoichiometrically cyclopropanate styrene with the same stereoselectivity as in the catalytic process is further evidence for it as an important species in the catalytic cycle. 12 refs., 1 tab.

• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6215432
• Journal Information: Journal of the American Chemical Society; (United States), Journal Name: Journal of the American Chemical Society; (United States) Vol. 115:6; ISSN JACSAT; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102 -- Chemical & Spectral Procedures
400201* -- Chemical & Physicochemical Properties
ALKANES
ALKENES
ALKYLATED AROMATICS
AROMATICS
CARBENES
CARBOXYLIC ACIDS
CATALYSIS
CHROMATOGRAPHY
COMPLEXES
CYCLOALKANES
DATA
DIAZO COMPOUNDS
ESTERS
EXPERIMENTAL DATA
GAS CHROMATOGRAPHY
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDROCARBONS
INFORMATION
MAGNETIC RESONANCE
NUCLEAR MAGNETIC RESONANCE
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OSMIUM COMPLEXES
PORPHYRINS
RADICALS
RESONANCE
SEPARATION PROCESSES
STYRENE
SYNTHESIS
TRANSITION ELEMENT COMPLEXES