Abstract
The present work provides a simple method for the characterization of alkylating agents by measuring the reaction selectivity toward 4-(p-nitrobenzyl) pyridine (NBP) in acetone containing phosphate buffer, evaluated in terms of the selectivity constant, SNBP, which is defined as log {[H2O]/[NBP]×N%/(100-N%)}, where N% is the percentage molar fraction of NBP alkylation. SNBP values were determined for about 40 kinds of halides, methanesulfonates, tosylates, sulfates, phosphates, nitrosoureas, and nitrosoguanidines. SNBP can replace the substrate constant, s, of the Swain-Scott equation, and SNBP's of some of the agents examined here were linearly correlated with the s values.
