CHARGE CONTROL OF PHENOL COMPLEXATION WITH UNSATURATED-COMPOUNDS CONTAINING ORGANOSILICON SUBSTITUENTS - THIOPHENE DERIVATIVES

The frequency shifts Delta nu of the O-H stretching modes and the reso nance components Delta nu(R) Of these shifts in the IR spectra of H-co mplexes of phenol with thiophene derivatives having organic and organo silicon substituents have been analyzed. Relationship of Delta nu and Delta nu(R) parameters to values calculated by nonempirical methods th at characterize the electronic effect of organic substituents on the e ffective charges of the thiophene ring atoms has been established. It has been shown that in the complexation of phenol (hard acid) with thi ophene derivatives charge control prevails over frontier orbital contr ol. The changes in the effective charges of the thiophene ring atoms d ue to the effect of organosilicon substituents have been calculated.