Synthesis and characterization of new tetraalkylaminophosphonium chlorides

GRAPHICAL ABSTRACT

ABSTRACT

New tetraalkylaminophosphonium chlorides were readily prepared by four-fold condensation of commercially available [P(CH₂OH)₄]Cl with a range of fifteen aryl based primary amines, in EtOH, at ambient temperature. All compounds have been characterized by FT–IR spectroscopy and elemental analysis. Solution ³¹P{¹H} NMR studies of these chloride salts reveal their instability with respect to various P^III/P^V species. The structures of three examples have been determined by single crystal X-ray diffraction and confirm the pseudotetrahedral arrangement around the P^V center. Extensive N–H···Cl hydrogen bonding is observed.

KEYWORDS:

• Phosphonium salts
• hydrogen bonding
• NMR spectroscopy
• X-ray crystallography
• aromatic amines

Acknowledgments

We thank Solvay (Dr. Ranbir Padda) for the kind donation of THPC. Dr. Mateusz Pitak at the EPSRC National Crystallography Service (University of Southampton) is acknowledged for data collection.

Funding

We would like to thank Loughborough University and Niger Delta University, Bayelsa State, Nigeria, for funding (A.T.E.; N.L.C). IIT Bombay Summer Research Placement (A.M.) and the Erasmus Exchange Programme (J.C.S.; A.M.I.R.; M.A.P.F.) are both acknowledged for their support.