168280-44-2Relevant articles and documents
A conformational study of cyclohexane-1,3,5-tricarbonitrile derivatives
Chuang, Tsung-Hsun,Fang, Jim-Min
, p. 193 - 200 (2001)
Cyclohexane-1,3,5-tricarbonitrile reached equilibrium having 1,3-cis-1,5-cis and 1,3-cis-1,5-trans isomers in a ratio of 3:7. The cis,cis-isomer preferred the conformation with three equatorial cyano groups, whereas the cis,trans-isomer displayed two cyano groups on equatorial positions and another cyano group on axial position. Condensation of cis,cis-cyclohexane-1,3,5-tricarbonitrile with L-(S)-valinol by the catalysis of ZnCl2 in refluxing 1,2-dichlorobenzene afforded two isomeric cyclohexane-1,3,5-trioxazolines in favor of the 1,3-cis-1,5-trans isomer. Metalation of cis,cis-cyclohexane-1,3,5-tricarbonitrile, followed by alkylations with dimethyl sulfate, benzyl bromide or allyl bromide, gave the corresponding trialkylation products with predominance of 1,3-cis-1,5-trans isomers. The cis,trans-isomer showed two cyano groups on axial positions and another cyano group on equatorial position, whereas the cis,cis-isomer exhibited three axial cyano groups. Treatment of trimethyl cis,cis-cyclohexane-1,3,5-tricarboxylate with lithium diisopropylamide and dimethyl sulfate afforded mainly the trimethyl ester of Kemp's triacid, which showed three axial carboxylate groups. Two competitive factors, i.e. the steric effect of incoming electrophiles and the dipole-dipole interactions of the cyano or carboxylate groups, might interplay to give different stereoselectivities in these reaction systems.
Synthesis and Complexation Behavior of the Functionalized Tripodal Phosphane cis,cis-1,3,5-Tris(cyano)-1,3,5-tris(diphenylphosphanyl)cyclohexane (tdppcycn)
Mayer, Hermann A.,Stoessel, Philipp,Fawzi, Riad,Steimann, Manfred
, p. 719 - 724 (2007/10/03)
The synthesis of the novel potentially bistripodal ligand cis,cis-1,3,5-tris(cyano)-1,3,5-tris(diphenylphosphanyl)cyclohexane (tdppcycn) (6) is described.Starting from the tricarboxylic acid cis,cis-1,3,5-C6H9(COOH)3 (1), which is converted stepwise into triacid chloride cis,cis-1,3,5-C6H9(COCl)3 (2), the triphenyl ester cis,cis-1,3,5-C6H9(COOPh)3 (3), the tricarboxamide cis,cis-1,3,5-C6H9(CONH2)3 (4), and the tricarbonitrile cis,cis-1,3,5-C6H9(CN)3 (5), we obtained tdppcycn (6) by α-deprotonation of 5 followed by treatment with ClPPh2 in good yield.Treatment of 6 with Mo(CO)3(η6-C7H8) and Ir(PPh3)2(CO)Cl gave octahedral Mo(tdppcycn)(CO)3 (7) and pentacoordinate Ir(tdppcycn)(CO)Cl (8), respectively, with a facially P-coordinated tdppcycn ligand.The stereochemistry of compounds 2-8 was established by 1H-, 13C-, 31P-NMR, and IR spectroscopy.An X-ray crystal structure analysis of complex 8 confirms the trigonal-bipyramidal ground-state structure in the solid state. - Keywords: Phosphane ligands, tripodal; Molybdenum complexes; Iridium complexes
