Inorg. Chem. 1991,solve as the solution is neutralized carefully to pH = 7.0. Evaporation in a rotary evaporator at aspirator vacuum and temperature less than 30 OC left a solid that was then pumped under high vacuum for several hours to remove traces of water. The solid was extracted with chloroform and the solvent removed under high-vacuum pumping to leave a semisolid. Stirring with a few drops of water caused crystallization to white crystals that were then dried under high vacuum, giving 1.20 g (80%) of Me2NCH2BH2NMe2CH2BHCONH2 (4). A sublimed sample (65-70 OC/high vacuum) melted sharply at 158-1 59 OC as opposed to a melting range beginning at 127 OC for the product as obtained, even though the infrared spectra were identical. NMR data: 'H NMe2 2.85, 2.69, 2.65, 2.61; NH2 broad doublet 5.5 and 5.4; CHI broad ca. 1:3:3:1 quartet 2.42, broad ca. I :2: 1 triplet I .90; "B unsymmetrical and shouldered triplet -8.4, -9.4, -10.0 decouples to a singlet -8.9. GC/MS data: one major GC peak and one minor one; m/e 184 (21%) and 183 (11%) parent -1 with 11B2 and 1°B1lB isotopic composition; 141 (100%) and 140 (52%) parent -1 for 1. Infrared data (cm-I) : N H 3435, 3282, 3166 s; BH 2343/2313 s with multiple shoulders; amide carbonyl 1621, 1575 s; 1306 w with shoulders, 1235 w, 1175 w, 1330-1320 m doublet, 1070 m multiplet, 1030-IOIO m doublet, 966 m, 930 m, 889 w, 852 m, 830 w, 734 m. If the basic hydrolysis solution is treated with 1 M HCI to approximately 0.15 M H+, the carboxylate derivative Me,NCH,BH,CH,NMe,BHCO?H (3) settles slowly from the solution Contribution from the
