Reactions of Amino-imino-boranes with Transition Metal Halides and Substituted Transition Metal Halides
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چکیده
The aminoiminoborane tmp-B=NCMe3 (1) adds to TiBr4 or ZrCL in a 1:1 ratio while PdCh adds 1 in a 1:2 ratio. In these new compounds the NBN unit is almost linear and the configuration corresponds to an allene. On the other hand 1 and Ti(OR)4 compounds and Ti(NMe2)4 give N metallated diaminoboranes tmp-B(X)-NCMe3EX3 (X = OR, NMe2). Mixed compounds Ti(OR)3_„X„ lead to diaminoboranes with BOR groups while the TiCl bond inserts into the B=N bond of 1 to produce tmp-BNMe2-NCMe3TiCl3. Hydrolysis of this compound leads to a spirocyclic dititanoxane with a short linear Ti-O-Ti bond and pentacoordinated Ti centers carrying two Cl atoms each. Spirocycles with a BN2E (E = Ti, Nb, Ta, Pd) unit are formed when 1 is allowed to react with TiCU, NbCls, TaCls and PdCh. The palladium compound 16 is dimeric, and dimerization occurs via Pd-Cl bridges. The aminoiminoborane tmp-B=NC6H3-2,6-/Pr2 reacts with the titanium compounds in the same manner as 1, however without formation of spirocycles.
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