Studies On The [3+2] Cyclic Addition Between Benzyne And α-Diazophosphonates

In this dissertation. o-Trimethylsilylphenyl triflate was used to generate benzyne in situ under the action of fluoride reagent, the [3+2] cyclic addition between benzyne and a-diazophosphonates is presented. After alteration of the substrates and controlling the reaction conditions, the [3+2] cyclic addition between benzyne and a-diazomethylphosphonates was tend to form a variety of 3-substituted benzo-[b]indazole compounds with high yield (up to 96%) by eliminating the phosphate groups. The [3+2] cyclic addition between benzyne and a-diazoisopropylphosphonates was mainly furnished with benzo-[b]indazoles containing 3,3-disubstituted quaternary carbon involving phosphate group with high yield (up to 99%). This system has general substrate accommodation.