TRIFLUOROMETHYLBORANE ADDUCTS OF GLYCINE

The N-borylated glycine derivatives (CF3)(2)((t)BuCH(2)CH(2))B . NHMeC H(2)COOH (I), (CF3)(3)B . NH2CH2COOH . H2O (II) and (CF3)(2)HB . NMe(2 )CH(2)COOH (III) have been prepared by the following routes. Hydrolysi s of (CF3)(2)((t)BuCH(2)CH(2))B . N=CH2CH3 yielded (CF3)(2)((t)BuCH(2) CH(2))B . NH(2)Me (IV), the nitrogen of which was alkylated by BrCH(2) COO(t)Bu/MeLi to form the glycine ester (CF3)(2)((t)BuCH(2)CH(2))B . N HMeCH(2)COO(t)Bu (V). (CF3)(3)B . NHEt(2) has been treated with KOH/Br -2 to yield (CF3)(3)B . NH3, which was alkylated by BrCH(2)COO(t)Bu/Me Li to form the thermally unstable ester (CF3)(3)BNH(2)CH(2)COO(t)Bu (V I). Similarly K+[(CF3)(2)HBNMe(2)](-) has been alkylated by BrCH(2)COO (t)Bu to yield (CF3)(2)HB . NMe(2)CH(2)CO(t)Bu (VII). Treatment of V-V II with CF3COOH furnished the free acids I-III. Compounds I-VII have b een characterized by elemental analyses, mass, IR and multinuclear NMR spectroscopy.