Аннотация:The simple synthetic procedure for preparation of -aryl--diazophosphonates via diazo transfer reaction is proposed. Benzylphosphonates reacted with tosyl azide (TsN3) in the presence of potassium tert-butoxide (KOtBu) to afford diazophosphonates in a yield up to 79%. The proposed method is general. The reaction uses easily available starting materials, tolerates various functional groups and may be applied for multi-gram scale synthesis.