TOPOLOGICAL INDEXES AND R(M) VALUES FOR PREDICTION OF THE PK(A) VALUES OF ISOMERIC METHYLPHENOLS, CHLOROPHENOLS, AND NITROPHENOLS .10.

Selected isomeric methylphenols, chlorophenols and nitrophenols have b een separated by TLC on silanized silica gel and the pK(a) values of t he compounds correlated with R(M), values and with numerical values of the topological indexes: M, (0) chi(v), (1) chi(v), (2) chi(v), W, I- B, A, B-0, B-1, B-2, and B-2(q).The most accurate prediction of the pK (a) values of the phenols investigated was achieved by use of biparame tric equations employing R(M) values and the topological indexes M or B-0.