BORON DERIVATIVES OF 3-FERROCENYLPYRAZOLE

3-Ferrocenylpyrazole (=Hpz*) has been prepared and was converted to the salt Kpz* and the complex [(pi-CH2CCH3CH2)Pd-(pz*)]2. In many respects Hpz* reacts with boron compounds in a manner similar to the unsubstituted parent pyrazole. Thus, the pyrazaboles R2B(mu-pz*)2BR2 (R = H, C2H5); the adducts (CH3)2HN.B(pz*)(C2H5)2, (CH3)2HN.B(pz*)(C8H14) (where C8H14BH = 9-borabicyclo[3.3.1]nonane), Hpz*.B(pz*)(C8H14), and (CH3)2HN.B(pz*)3; the salts Tl[(pz*)2BH2], K[(pz*)2B(C2H5)2], and M[(pz*)2B(C8H14)] (M = Na, K); and the complexes (C2H5)2(mu-pz*)2Pd(pi-CH2CHCH2) and (C8H14)B(mu-pz*)2Pd(pi-CH2CHCH2) have been prepared and characterized. On the other hand, the relative liability of the ferrocenyl unit of Hpz* prevents some reactions that are possible with other pyrazoles, e.g., formation of K[HB(pz*)3] or K[B(pz*)4] from Hpz* and KBH4 or the halogenation at the boron sites of H2B(mu-pz*)2BH2.