Author/Authors :
Ana M. Plut??n، نويسنده , , Heidy M?rquez، نويسنده , , Estael Ochoa، نويسنده , , Margarita Morales، نويسنده , , Mairim Sosa، نويسنده , , Lourdes Mor?n، نويسنده , , Yolanda Rodr??guez، نويسنده , , Margarita Su?rez، نويسنده , , Nazario Mart??n، نويسنده , , Carlos Seoane، نويسنده ,
Abstract :
A study of the behaviour towards alkylation of a series of benzoyl and furoylthioureas with 3,3-disubstitution has been carried out using NMR determinations. X-Ray data and semiempirical theoretical calculations demonstrated that the most stable conformation for these molecules is the so-called quasi-S. Also an explanation of the high selectivity towards the S-alkylation of these systems, based on the high contribution of the sulphur atom to the HOMO in acylthioureas is given for the title compounds. Steric factors are responsible for the difference between the percentages obtained for the S-alkylated product in 1-(4-methylbenzoyl)-3,3-diethylthiourea and 1-benzoyl-3,3-dibenzylthiourea.
Keywords :
Alkylation , polydentate system , Thioureas , Theoretical calculations
