SYNTHESES AND COORDINATION ABILITY OF SOME 1,5-CYCLOPOLYMETHYLENETETRAZOLES

A series of 1,5-cyclopolymethylenetetrazoles were synthesized with the hydrocarbon chain containing 3,4, 6, 7, 8, 9, and 11 methylene groups. The donor properties of these compounds were investigated by spectrophotometric measurements of the tetrazole-iodine charge-transfer complex formation constants in the 5-35° interval. The solvent was 1,2-dichloroethane. The enthalpy and the entropy changes for the complexing reactions were determined from the temperature coefficient of the stability constant. The donor properties of tetrazoles were rather weak and the formation constant values at 25 ° ranged from 1.42 to 2.641. mol-1. There does not seem to be a simple correlation between the length of the hydrocarbon chain and the stability of the iodine complex. © 1968, American Chemical Society. All rights reserved.