174683-71-7Relevant academic research and scientific papers
Optically active transition metal compounds 113: Synthesis of chiral carbonylnitrosylcobalt complexes with four different unidentate ligands
Brunner, Henri,Faustmann, Peter,Nuber, Bernhard
, p. 129 - 140 (1998)
In a two step synthesis pairs of diastereomers Co(CO)(NO)(L)(L*), which differ only in the configuration at the cobalt atom, are obtained from Co(CO)3(NO). L is a monodentate phosphite or phosphane and L* a monodentate optically active phosphane or isocyanide. For complex 8 (L=PPh3, L=phenyl-tarpholane) a diastereomer ratio of 55:45 (8a:8b) is found after the synthesis. For all other complexes this ratio is 50:50. By crystallization it is possible to obtain samples enriched in one of the diastereomers of 1 (L=P(OMe)3, L=PPh2N(Me)CH(Me)(Ph)), 2 (L=PPh3, L=CNCH(Me)(Ph)), 7 (L=PMe2Ph, L=glyphos) and 8. The ratios achieved are 74:26 (1a:1b), 79:21 (2a:2b), 71:29 (7a:7b) and 74:26 (8a:8b). The crystal structures of six complexes were determined. For (SCo,SC)-2a, (RCo,SC)-3b and (SCo,RC,RC)-8a the absolute configuration could be established. The cobalt center is configurationally stable at room temperature. Epimerization is observed only at higher temperatures. 1a epimerizes in toluene-d8 at 82.2°C with a half life of τ1/2=43 h, 2a in benzene-d6 at 72.9°C with τ1/2=83 min and 7a in benzene-d6 at 70.0°C with τ1/2=77 min.
Diphenylphosphine derivatives of Co( NO) ( CO) 3, Fe( NO) 2( CO) 2 and Mn( NO) ( CO) 4
Lin, Jiann T.,Wang, Shiow Y.,Chou, Yung C.,Gong, Ming L.,Shiow, Yui-May,Gau, Han-Mou,Wen, Yuh S.
, p. 183 - 193 (2007/10/03)
The complexes Co(NO)(CO)(Ph2PH)2 (1), Fe(NO)2(Ph2PH)2 (2) and Mn(NO)(CO)2(Ph2PH)2 (3) are synthesized from Co(NO)(CO)3, Fe(NO)2(CO)2 and Mn(NO)(CO)4 respectively. Deprotonation of 1 with two equivalents of BuLi followed by subsequent addition of methyl iodide, allyl bromide and propargyl bromide provides Co(NO)(CO)(Ph2PMe)2 (4), Co(NO)(CO)(Ph2PCH2CHCH2)2 (5) and Co(NO)(CO)(Ph2PCH2CCH)2 (6) respectively. X-ray crystal structure analyses for 1, 3 and 4-6 were carried out to give data as followed. 1: monoclinic; C2/c; Z = 4; a = 17.130(5), b = 9.894(2) and c = 42.607(1) A; β = 93.29(2)°; V = 7210(2) A3; R = 0.056; Rw = 0.058. 3: monoclinic; C2/c; Z = 4; a = 15.231(5), b = 10.247(2) and c = 16.311(2) A; β = 102.29(2)°; V= 2488(1) A3; R = 0.041; Rw = 0.042. 4: monoclinic; C2/c; Z = 4; a = 15.556(3), b = 12.072(1) and c = 14.809(2) A; β 114.43(1)°; V= 2532.0(7) A3; R = 0.032; Rw = 0.031. 5: monoclinic; P21/c; Z = 4; a = 15.427(2), b = 10.118(2) and c = 18.793(6) A; β = 102.56(1)°; V = 2863(1) A3; R = 0.042; Rw = 0.046. 6: monoclinic; P21/n; Z = 4; a = 9.3393(8), b = 19.035(4) and c = 16.007(1) A; β = 94.912(7)°; V= 2845.8(6) A3; R = 0.052; Rw = 0.059.
