Proazaphosphatrane P(RNCH2CH2)3N (R=Me, i-Pr)-catalyzed isomerization of allylaromatics, allyl phenyl sulfide, allyl phenyl sulfone, and bis-allylmethylene double bond-containing compounds

Using a proazaphosphatrane catalyst, P(RNCH2CH2)(3)N (R=Me, i-Pr), allylaromatics and allyl phenyl sulfide were selectively isomerized to the corresponding vinyl isomers in yields up to > 99% in CH3CN at 40 degrees C. Efficient transformation of allyl phenyl sulfone at ambient temperature afforded an isomerization/dimerization product in > 95% yield. Conjugation of bis-allylmethylene double bond-containing compounds gave the corresponding conjugated isomers for cis,cis-9,12-octadecadienol and its methyl ether in yields up to 97%, and desilylation/conjugation products were obtained from the catalytic reaction of the trimethylsilyl ether of cis,cis-9,12-octadecadienol. The reaction mechanism is discussed based upon the H-1 and P-31 NMR-monitored reactions in CD3CN or CH3CN under the reaction conditions.