Amine borane Crystal structure

Reduction of dichloro-NN -ethylenebis(salicylideneiminato)titanium(rv) by BH4 gives a compound which analyses as [Ci6Hi N202Ti(BH3)2]2. The crystal structure of this showed the presence of amine-boranes as donor groups, and the novel unit (19) in the complex. ... 

The in-out and out-out forms have been detected in the crystal structures of N-borane-[l.l.l] and N,N-diborane-[2.2.2] where BHj groups are attached to the amine nitrogens. 

An example of the exo-exo configuration is seen with the bis(borane-amine) derivative of [2.2.2]cryptand (Figure 7c) in which both of the large borohydride groups point away from the cavity. In contrast, the mono(borane-amine) derivative of [l.l.l]cryptand takes up an endo-exo structure in the crystal (78NJC615). 

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