Premium
Versatile Supramolecular Coordination Behaviour of a Bis(bidentate) Tetraphosphane
Author(s) -
Strabler Christof,
Ortner Teresa,
Prock Johannes,
Granja Alvaro,
Gutmann Rene,
Kopacka Holger,
Müller Thomas,
Brüggeller Peter
Publication year - 2013
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.201300636
Subject(s) - cyclobutane , chemistry , denticity , dimethoxyethane , moiety , supramolecular chemistry , stereochemistry , medicinal chemistry , cis–trans isomerism , coordination complex , ring (chemistry) , crystallography , crystal structure , metal , organic chemistry , electrode , electrolyte
The bis(bidentate) phosphane cis , trans , cis ‐1,2,3,4‐tetrakis(diphenylphosphanyl)cyclobutane (dppcb) has been used for the synthesis of supramolecular complexes, so‐called dyads and triads. Depending on the monometallic precursor compound [Ru(bpy) 2 (dppcb)](PF 6 ) 2 or [Ru(bpy) 2 ( cis ‐dppcbO 2 )](PF 6 ) 2 [bpy = 2,2′‐bipyridine, cis ‐dppcbO 2 = cis , trans , cis ‐1,2‐bis(diphenylphosphanoyl)‐3,4‐bis(diphenylphosphanyl)cyclobutane], [Ru(bpy) 2 (dppcb)NiBr 2 ](PF 6 ) 2 ( 1 ) or ΔΛ/ΛΔ‐[{Ru(bpy) 2 ( cis ‐dppcbO 2 )} 2 NiBr](PF 6 ) 5 ( 2 ) is exclusively formed in good yield by reaction with [NiBr 2 (DME)] (DME = dimethoxyethane). The versatile coordination behaviour of dppcb compared with that of cis ‐dppcbO 2 is confirmed by cis , trans , cis ‐2,3‐bis(diphenylphosphanoyl)‐1,4‐bis(diphenylphosphanyl)cyclobutane (2,3‐ trans ‐dppcbO 2 , 4 ). Although two dppcb ligands coordinated simultaneously to a Pd II centre cannot produce a square‐planar PdP 4 core, the reaction of two equivalents of 4 with [Pd(CH 3 CN) 4 ](BF 4 ) 2 exclusively leads to meso ‐(MMMP/MPPP)‐[Pd(2,3‐ trans ‐dppcbO 2 ‐ P , P′ ) 2 ](BF 4 ) 2 ( 3 ). This means that trans configurations of coordinating 2,3‐ trans ‐dppcbO 2 with respect to the cyclobutane rings allow the formation of this PdP 4 moiety. However, in the case of 4 it is also possible to obtain [PdCl 2 (2,3‐ trans ‐dppcbO 2 ‐ P , P′ )] ( 5 ) in excellent yield by using [PdCl 2 (COD)] (COD = cyclooctadiene). In 5 , only one ligand 4 is attached to the Pd II centre, and a trans configuration of 4 within the five‐membered chelate ring can again be seen. All solid‐state structures 1 – 5 have been determined by single‐crystal X‐ray structure analysis. The corresponding solution structures are in agreement with these solid‐state structures and have been authenticated by multinuclear NMR spectroscopy, FAB and MALDI‐TOF‐MS measurements, UV/Vis spectroscopy and cyclic voltammetry. In the case of 2 , the emission and lifetime properties of the excited state indicate that triads such as 2 could be suitable catalysts for the reductive part of water splitting.