TY - JOUR
T1 - Synthesis, structure, spectroscopy, and reactivity of oxapentadienyl- cobalt-phosphine complexes
AU - Bleeke, John R.
AU - Lutes, Bryn L.
AU - Lipschutz, Michael
AU - Sakellariou-Thompson, Donastas
AU - Lee, John Seonghyun
AU - Rath, Nigam P.
PY - 2010/11/8
Y1 - 2010/11/8
N2 - The first examples of oxapentadienyl-cobalt complexes have been synthesized and structurally characterized. Treatment of (Cl)Co(PMe3) 3 with potassium oxapentadienide produces ((1,2,3-η)-5- oxapentadienyl)Co(PMe3)3 (1), while the reaction of (Cl)Co(PMe3)3 with potassium 2,4-dimethyloxapentadienide generates ((1,2,3-η)-2,4-dimethyl-5-oxapentadienyl)Co(PMe3) 3 (2). Both 1 and 2 undergo ligand substitution reactions when treated with excess carbon monoxide. Compound 1 reacts with 1 equiv of CO to produce ((1,2,3-η)-5-oxapentadienyl)Co(PMe3)2(CO) (3), while 2 undergoes a double CO substitution to generate ((1,2,3-η)-2,4- dimethyl-5-oxapentadienyl)Co(PMe3)(CO)2 (4). Compound 3 can also be synthesized by reacting (Cl)Co(PMe3)2(CO) 2 with potassium oxapentadienide, but the analogous reaction involving potassium 2,4-dimethyloxapentadienide results in reduction of the cobalt starting material and production of the Co(0) dimer (CO)(PMe 3)2Co(μ-CO)2Co(PMe3) 2(CO) (5). Treatment of 1 with triflic acid (HO3SCF 3) or methyl triflate (MeO3SCF3) results in electrophilic attack at oxygen and production of (η4-butadienol) Co(PMe3)3+O3SCF3 - (6) or (η4-butadienyl methyl ether)Co(PMe 3)3+O3SCF3- (7). Treatment of 2 with triflic acid or methyl triflate also results in electrophilic attack at oxygen; however, these products are unstable and rapidly lose their protonated or methylated ligands. The resulting Co(PMe 3)4+O3SCF3-, generated in situ, reacts with excess carbon monoxide to produce Co(PMe 3)3(CO)2+O3SCF 3- (8). Compounds 1-8 have been characterized by single-crystal X-ray diffraction.
AB - The first examples of oxapentadienyl-cobalt complexes have been synthesized and structurally characterized. Treatment of (Cl)Co(PMe3) 3 with potassium oxapentadienide produces ((1,2,3-η)-5- oxapentadienyl)Co(PMe3)3 (1), while the reaction of (Cl)Co(PMe3)3 with potassium 2,4-dimethyloxapentadienide generates ((1,2,3-η)-2,4-dimethyl-5-oxapentadienyl)Co(PMe3) 3 (2). Both 1 and 2 undergo ligand substitution reactions when treated with excess carbon monoxide. Compound 1 reacts with 1 equiv of CO to produce ((1,2,3-η)-5-oxapentadienyl)Co(PMe3)2(CO) (3), while 2 undergoes a double CO substitution to generate ((1,2,3-η)-2,4- dimethyl-5-oxapentadienyl)Co(PMe3)(CO)2 (4). Compound 3 can also be synthesized by reacting (Cl)Co(PMe3)2(CO) 2 with potassium oxapentadienide, but the analogous reaction involving potassium 2,4-dimethyloxapentadienide results in reduction of the cobalt starting material and production of the Co(0) dimer (CO)(PMe 3)2Co(μ-CO)2Co(PMe3) 2(CO) (5). Treatment of 1 with triflic acid (HO3SCF 3) or methyl triflate (MeO3SCF3) results in electrophilic attack at oxygen and production of (η4-butadienol) Co(PMe3)3+O3SCF3 - (6) or (η4-butadienyl methyl ether)Co(PMe 3)3+O3SCF3- (7). Treatment of 2 with triflic acid or methyl triflate also results in electrophilic attack at oxygen; however, these products are unstable and rapidly lose their protonated or methylated ligands. The resulting Co(PMe 3)4+O3SCF3-, generated in situ, reacts with excess carbon monoxide to produce Co(PMe 3)3(CO)2+O3SCF 3- (8). Compounds 1-8 have been characterized by single-crystal X-ray diffraction.
UR - https://www.scopus.com/pages/publications/78149312721
U2 - 10.1021/om100361a
DO - 10.1021/om100361a
M3 - Article
AN - SCOPUS:78149312721
SN - 0276-7333
VL - 29
SP - 5057
EP - 5067
JO - Organometallics
JF - Organometallics
IS - 21
ER -