TY - JOUR
T1 - Half-sandwich ruthenium(II) catalysts for C-C coupling reactions between alkenes and diazo compounds
AU - Baratta, Walter
AU - Herrmann, Wolfgang A.
AU - Kratzer, Roland M.
AU - Rigo, Pierluigi
PY - 2000/9/4
Y1 - 2000/9/4
N2 - The complex [(η5-C5H5)Ru(PPh3) 2Cl] (1) and other readily available ruthenium(II) derivatives of general formula [(η5-ligand)Ru(PR3)2X] efficiently catalyze the cyclopropanation of styrene and other electron-rich alkenes in the presence of ethyl diazoacetate with a high cis stereoselectivity. When diphenyldiazomethane is employed as carbene source, the reaction with styrene, catalyzed by 1, affords mainly 1,1,3-triphenylpropene, as result of a formal :CPh2-:CHCH2Ph coupling. Furthermore, appreciable amounts of the metathesis and, cyclopropanation products 1,1-diphenylethene and 1,2-diphenylcyclopropanes in a 1,1 molar ratio are observed. The carbene complex [(η5-C5H5)Ru(=CPh2)(PPh 3)Cl] (13), which was detected during the catalytic process, can be readily obtained in 85% isolated yield from 1 and diphenyldiazomethane in a one-pot reaction. With styrene, complex 13 undergoes a stoichiometric carbene transfer reaction, yielding the same organic products observed in the catalytic process with 1.
AB - The complex [(η5-C5H5)Ru(PPh3) 2Cl] (1) and other readily available ruthenium(II) derivatives of general formula [(η5-ligand)Ru(PR3)2X] efficiently catalyze the cyclopropanation of styrene and other electron-rich alkenes in the presence of ethyl diazoacetate with a high cis stereoselectivity. When diphenyldiazomethane is employed as carbene source, the reaction with styrene, catalyzed by 1, affords mainly 1,1,3-triphenylpropene, as result of a formal :CPh2-:CHCH2Ph coupling. Furthermore, appreciable amounts of the metathesis and, cyclopropanation products 1,1-diphenylethene and 1,2-diphenylcyclopropanes in a 1,1 molar ratio are observed. The carbene complex [(η5-C5H5)Ru(=CPh2)(PPh 3)Cl] (13), which was detected during the catalytic process, can be readily obtained in 85% isolated yield from 1 and diphenyldiazomethane in a one-pot reaction. With styrene, complex 13 undergoes a stoichiometric carbene transfer reaction, yielding the same organic products observed in the catalytic process with 1.
UR - http://www.scopus.com/inward/record.url?scp=0001109251&partnerID=8YFLogxK
U2 - 10.1021/om0003537
DO - 10.1021/om0003537
M3 - Article
AN - SCOPUS:0001109251
SN - 0276-7333
VL - 19
SP - 3664
EP - 3669
JO - Organometallics
JF - Organometallics
IS - 18
ER -