PART I: KINETICS OF AUTOCATALYZED AND CATALYZED ARBUZOV REARRANGEMENTS USING PHOSPHOROUS AND PROTON NMR. PART II: SYNTHESIS AND REACTIONS OF IMMOBILIZED, ALKOXY TRIPHENYLPHOSPHONIUM TRIFLATES AND ALKYL P-TOLUENESULFONATES
HAMP, DONALD WESLEY
Doctor of Philosophy
Part I. Rates for the methyl rearrangement: ABPOMe (--->) ABMeP=O, A,B=Me,t-Bu, Et, Ph, OMe, OPh as catalyzed by methyl iodide (I), dimethyl sulfate (II), and methyl trifluoromethanesulfonate (III), were determined using proton and phosphorus NMR. Four distinct elementary steps for the rearrangement were found. Three correspond to a normal Arbuzov rearrangement, alkylation of the trivalent ester to yield the alkoxyphosphonium salt; followed by a reversible intramolecular decomposition of the intermediate to phosphonate and alkyl halide. The fourth step is the autocatalytic pathway: k(,3) ABMeP('+)OMe + ABPOMe (--->) ABMeP=O + ABMep('+)OMe With (I) as the catalyst k(,3) is insignificant, the reaction following the traditional two step mechanism. k(,3)'s importance when (II) is the catalyst depends upon the ligands A and B and also on concentration. (III) yields a purely autocatalytic mechanism except when A, B = PhO. LFE plots were constructed for the quaternization of phosphines and trivalent phosphorus esters using (I), (II), (III), and ethyl iodide. The observed lack of selectivity (constant (rho)(,I)) can be rationalized using a nonconcerted S(,N)2 displacement mechanism. Part II. Compounds of the type Poly-P('+)Ph(,2)OR ('-)OTf (IV) were synthesized from Amberlite XE-305. (IV), with R = primary alkyl, reacted with halogen and thiocyanate anions in CH(,2)Cl(,2) and Ch(,3)CN to yield alkyl halides and alkyl thiocyanates in yields comparable to those obtained for the monomeric analog. Dowex 50X2-200 and Amberlyst XN-1010 cation exchange resins were converted in high yields to the immobilized sulfonyl chloride form using PCl(,5) in o-dichlorobenzene at 110(DEGREES)C for 24 hrs. The sulfonyl chlorides reacted rapidly with amines and alcohols, to give sulfonate esters and sulfonamides. Conversion of Nafion (H('+)) to the sulfonyl chloride form using PCl(,5) was unsuccessful as were attempts to form the alkyl ester by treating Nafion (H('+)) with AgNO(,3) followed by RI, or CH(,2)N(,2) in ether.