First allylboration of organic compounds with the Ndouble bond; length as m-dashN double bond. Synthesis of N-allylpyrazolidines and allyl-1,2-diphenylhydrazine

Triallylborane adds to the Ndouble bond; length as m-dashN double bond of pyrazolines 1 and 2 at 0 °C giving after deboronation the corresponding N-allylpyrazolidines 4 and 5. Further transformations of allylpyrazolidine 4 including the cyclopropane ring opening were studied. Allylboration of azobenzene with triallylborane gives rise to 1-allyl-1,2-diphenylhydrazine.