TY - JOUR
T1 - Activation of C-H bonds in thiophenes by Rh(PMe3)2(CO)Cl
T2 - A low-temperature NMR study
AU - Partridge, Martin G.
AU - Field, Leslie D.
AU - Messerle, Barbara A.
PY - 1996/1/23
Y1 - 1996/1/23
N2 - Irradiation of trans-Rh(PMe3)2(CO)Cl (1) at 230 K in the presence of 2,5-dimethylthiophene or thiophene affords products arising from C-H insertion. Irradiation of 1 in 2,5-dimethylthiophene affords three products: two conformers of the six-coordinate complex trans-Rh(PMe3)2(CO)(Cl)(2,5-dimethyl-3-thienyl)H, related by rotation about the Rh-C bond, and trans-Rh(PMe3)2(CO)(2,5-dimethyl-3-thienyl). The major conformer of trans-Rh(PMe3)2-(CO)(Cl)(2,5-dimethyl-3-thienyl)H decays back to 1 at a rate of (2.9 ± 0.2) × 10-4 s-1 at 273 K, whereas the minor conformer and trans-Rh(PMe3)2(CO)(2,5-dimethyl-3-thienyl) are relatively stable. Irradiation of (1) in the presence of thiophene affords products arising from addition at both the 2- and 3-positions in the thiophene ring: trans-Rh(PMe3)2(CO)-(Cl)(2-thienyl)H, Rh(PMe3)2(CO)(Cl)(3-thienyl)H and trans-Rh(PMe3)2(CO)(2-thienyl). The six-coordinate Rh(III) species each exist as two rotamers at 230 K related by rotation about the Rh-Caryl bond. Irradiation of 1 in thiophene or 2,5-dimethylthiophene under nitrogen with UV light at low temperatures also gives rise to products arising from thiophene carbonylation.
AB - Irradiation of trans-Rh(PMe3)2(CO)Cl (1) at 230 K in the presence of 2,5-dimethylthiophene or thiophene affords products arising from C-H insertion. Irradiation of 1 in 2,5-dimethylthiophene affords three products: two conformers of the six-coordinate complex trans-Rh(PMe3)2(CO)(Cl)(2,5-dimethyl-3-thienyl)H, related by rotation about the Rh-C bond, and trans-Rh(PMe3)2(CO)(2,5-dimethyl-3-thienyl). The major conformer of trans-Rh(PMe3)2-(CO)(Cl)(2,5-dimethyl-3-thienyl)H decays back to 1 at a rate of (2.9 ± 0.2) × 10-4 s-1 at 273 K, whereas the minor conformer and trans-Rh(PMe3)2(CO)(2,5-dimethyl-3-thienyl) are relatively stable. Irradiation of (1) in the presence of thiophene affords products arising from addition at both the 2- and 3-positions in the thiophene ring: trans-Rh(PMe3)2(CO)-(Cl)(2-thienyl)H, Rh(PMe3)2(CO)(Cl)(3-thienyl)H and trans-Rh(PMe3)2(CO)(2-thienyl). The six-coordinate Rh(III) species each exist as two rotamers at 230 K related by rotation about the Rh-Caryl bond. Irradiation of 1 in thiophene or 2,5-dimethylthiophene under nitrogen with UV light at low temperatures also gives rise to products arising from thiophene carbonylation.
UR - http://www.scopus.com/inward/record.url?scp=0001549817&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0001549817
VL - 15
SP - 872
EP - 877
JO - Organometallics
JF - Organometallics
SN - 0276-7333
IS - 2
ER -