Conformational And Electronic Interaction Studies Of Some P-substituted α-methylsulfonyl-α-diethoxyphosphorylacetophenones

The analysis of the IR carbonyl band of the α-methylsulfonyl-α-diethoxyphosphoryl p-substituted acetophenones p-Y-Ph-C(O)CH(SO2Me)[P(O)(OEt)2] (Y = OMe 1, H 2, F 3, Cl 4, Br 5 and NO2 6) supported by HF/6-31G(d,p) ab initio calculations of the α-methylsulfonyl-α-diethoxyphosphoryl acetophenone 2, indicated the existence of a single stable c1 conformer in gas phase and in solvents of increasing polarity, along with the presence of second less stable conformation in gas phase. The c1 conformer present the (SO2Me) group and the [P(O)(OEt2)] groups in a syn-clinal (gauche) geometry and is stabilised through of the Oδ-(CO)...Pδ+(PO), Oδ-[PO(OEt)]...Cδ+(CO), Oδ-(PO)...Cδ+(CO), Oδ-(CO)...Sδ+(SO2Me) and Oδ-(SO2)...Cδ+(CO) electronic interactions along with Hδ+(SO2Me).... Oδ-(CO), Hδ+(CH2)[POEt].... Oδ-(SO2Me), Hδ+(o-Ph).... Oδ-(CO) and Hδ+(o′-Ph).... Oδ-(PO) intramolecular hydrogen bonds. The almost constant negative carbonyl frequency shifts (Δν) for the title compounds 1-6 with respect to the parent acetophenones 7-14 corroborates the prevalence of the electronic interactions over the -Iσ inductive effect of the α-substituents for the title compounds and gives strong support for the existence of the crossed Oδ-(CO)...Sδ+(SO2Me) and Oδ-(SO2)...Cδ+(CO) (charge transfer and electrostatic); Oδ-(CO)...Pδ+(PO) and Oδ-[PO(OEt)]...Cδ+(CO), (electrostatic) interactions. © 2008 Elsevier B.V. All rights reserved.8921-3300304Distefano, G., Dal Colle, M., Bertolasi, V., Olivato, P.R., Bonfada, E., Mondino, M.G., (1991) J. Chem Soc., Perkin Trans., 2, p. 1195Olivato, P.R., Bonfada, E., Rittner, R., (1992) Magn. Reson. Chem., 30, p. 81Dal Colle, M., Bertolasi, V., de Palo, M., Distefano, G., Jones, D., Modelli, A., Olivato, P.R., (1995) J. Chem. Phys., 99, p. 15011Olivato, P.R., Guerrero, S.A., Rittner, R., (1997) Phosphorus Sulfur Silicon, 130, p. 155Olivato, P.R., Hui, M.LT., Rodrigues, A., Ruiz Filho, R., Rittner, R., Zukerman-Schpector, J., Distefano, G., Dal Colle, M., (2003) J. Mol. Struct., 645, p. 259Olivato, P.R., Reis, A.K.C.A., Ruiz Filho, R., Zukerman-Schpector, J., Rittner, R., (2004) J. Mol. Struct. (Theochem.), 677, p. 199Olivato, P.R., Ruiz Filho, R., Zuckerman-Schpector, J., Dal Colle, M., Distefano, G., (2001) J. Chem. Soc., Perkin Trans., 2, p. 97Jones, D., Dal Colle, M., Distefano, G., Ruiz Filho, R., Olivato, P.R., (2001) J. Organomet. Chem., 625, p. 121Olivato, P.R., Reis, A.K.C.A., Zukerman-Schpector, J., Tormena, C., Rittner, R., Domingues, N.L.C., Dal Colle, M., (2006) J. Mol. Struct., 798, p. 57Sega, E.M., Reis, A.K.C.A., Olivato, P.R., Rodrigues, A., Carvalho, J.E., Castilho, R.F., Rittner, R., Höehr, N.F., (2008) Clin. Chim. Acta, 389, p. 177Reis, A.K.C.A., Olivato, P.R., Rittner, R., (2005) Magn. Reson. Chem., 43, p. 85Galactic Industries Corporation, 1991-1998M.J. Frisch, G.W. Trucks, H.B. Schlegel, G.E. Scuseria, M.A. Robb, J.R. Cheeseman, V.G. Zakrzewski, J.A. Montgomery Jr., R.E. Stratmann, J.C. Burant, S. Dapprich, J.M. Millam, A.D. Daniels, K.N. Kudin, M.C. Strain, O. Farkas, J. Tomasi, V. Barone, M. Cossi, R. Cammi, B. Mennucci, C. Pomelli, C. Adamo, S. Clifford, J. Ochterski, G.A. Petersson, P.Y. Ayala, Q. Cui, K. Morokuma, D.K. Malick, A.D. Rabuck, K. Raghavachari, J.B. Foresman, J. Cioslowski, J.V. Ortiz, B.B. Stefanov, G. Liu, A. Liashenko, P. Piskorz, I. Komaromi, R. Gomperts, R.L. Martin, D.J. Fox, T. Keith, M.A. Al-Laham, C.Y. Peng, A. Nanayakkara, C. Gonzalez, M. Challacombe, P.M.W. Gill, B. Johnson, W. Chen, M.W. Wong, J.L. Andres, M. Head-Gordon, E.S. Repogle, J.A. Pople, Gaussian 98, Revision A.6, Gaussian, Pittsburg, PA, 1998Riddick, J.A., Bunger, W.B., (1970) Techniques of Organic Chemistry, vol. II: Organic Solvents. third ed., , Wiley, New YorkMarch, J., (1985) Advanced Organic Chemistry. third ed., , Wiley, New YorkHansh, C., Leo, A., Hoekman, D., (1995) Exploring QSAR Hydrophobic, Electronic and Steric Constants, , American Chemical Society, Washington, D