Pseudocryptand-type complexes of heterocyclic derivatives of bis(meta-phenylene)-32-crown-10 with diquat.

The readily prepared dipicolinate, diquinaldate, and dinaphthyridate ester derivatives 1c – 1e of bis( m -phenylene)-32-crown-10 (BMP32C10) diol 1b demonstrated improved association constants with diquat ( 3 ) compared with BMP32C10 itself ( 1a ). Importantly, the association constant of dinaphthyridyl BMP32C10 ( 1e ) with diquat is even higher than some BMP32C10-based cryptands, which are synthetically difficult to obtain. An unusual pseudocryptand-type alternating poly[2]pseudorotaxane was formed between 1e and diquat in the solid state. [ABSTRACT FROM AUTHOR]