Synthesis of a New, Bulky Tetraarylphosphonium, a Tetraarylborate, and Their Salt

Abstract

Tris(m-terphenyl-5′-yl)phosphine (2), tetrakis(m-terphenyl-5′-yl)phosphonium bromide (3), sodium tetrakis(m-terphenyl-5′-yl)borate (4), and the phosphonium borate salt 5 of 3 and 4 were synthesized, in the expectation of creating interionic spacings that have unusual electric fields. Characterization was achieved by NMR and FTMS, and, in the case of phosphine 2 and phosphonium bromide 3, via X-ray crystal structure analysis. The electrochemical properties of 2 were different from those of triphenylphosphine, even though the C-P-C bond angles of the two compounds are almost the same.

Key words

arylations - cations - dendrimers - electric field - bulky salt

References

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5

Attempted X-ray crystal structure analyses of 4 and 5 were unsuccessful, so their diameters and ionic center distances were estimated by PM3 calculation (geometry optimization).