173066-40-5Relevant academic research and scientific papers
Synthesis and Structural Characterization of [PhE(BNMe2)2]2 (E=P or As);Six-Membered P2B4 and As2B4 Rings with Unusual Structures
Moezzi, Afarin,Olmstead, Marylin M.,Pestana, Doris C.,Power, Philip P.
, (2008/10/08)
The reaction of either Li2PPh or Li2AsPh with the diborane(4) derivativeB2(NMe2)2Br2 affords the compounds [PhP(BNMe2)2]2 (1) or [PhAs(BNMe2)2] 2 (2) in good yield. Both 1 and 2 have cyclic structures featuring non-planar P2B4 or As2B4 six-membered rings which have chair conformations. Although all four borons in each ring have planar coordination the two phosphorus or arsenic centers have different degrees of pyramidalization. Bond distances within the rings indicate that the B-B, B-P or B-As bondsare single, whereas the exo B-N bonds lengths are consistent with signi ficant π-bonding. The ring structures of 1 and 2 are in sharp contrast to the related boron-nitrogen species (t-BuN)2N4Me4 which has a nido-N2B4 framework. The attempted synthesis of the nitrogen analogue of 1 or 2 by using a similar approach did not result in the isolation of [PhN(BNMe2)2]2, instead the tetramino diborane(4) species [B(NMe2)NHPh]2 (3), which has a structure similar to other tetramine diborane (4) compounds, was isolated.
