Sterically crowded peri-substituted naphthalene phosphines and their PV derivatives
Abstract
Three sterically crowded peri-substituted naphthalene phosphines, Nap[PPh2][ER] (Nap=naphthalene-1,8-diyl; ER=SEt, SPh, SePh) 1–3 , which contain phosphorus and chalcogen functional groups at the peri positions have been prepared. Each phosphine reacts to form a complete series of PV chalcogenides Nap[P(E′)(Ph2)(ER)] (E′=O, S, Se). The novel compounds were fully characterised by using X-ray crystallography and multinuclear NMR spectroscopy, IR spectroscopy and MS. X-ray data for 1 , 2 , n O , n S , n Se (n=1–3) are compared. Eleven molecular structures have been analysed by naphthalene ring torsions, peri-atom displacement, splay angle magnitude, X⋅⋅⋅E interactions, aromatic ring orientations and quasi-linear arrangements. An increase in the congestion of the peri region following the introduction of heavy chalcogen atoms is accompanied by a general increase in naphthalene distortion. P⋅⋅⋅E distances increase for molecules that contain bulkier atoms at the peri positions and also when larger chalcogen atoms are bound to phosphorus. The chalcogenides adopt similar conformations that contain a quasi-linear E⋅⋅⋅PC fragment, except for 3 O , which displays a twist-axial-twist conformation resulting in the formation of a linear O⋅⋅⋅SeC alignment. Ab initio MO calculations performed on 2 O , 3 O , 3 S and 3 Se reveal Wiberg bond index values of 0.02 to 0.04, which indicates only minor non-bonded interactions; however, calculations on radical cations of 3 O , 3 S and 3 Se reveal increased values (0.14–0.19).
Citation
Knight , F R , Fuller , A , Buehl , M , Slawin , A M Z & Woollins , J D 2010 , ' Sterically crowded peri -substituted naphthalene phosphines and their P V derivatives ' , Chemistry - A European Journal , vol. 16 , no. 25 , pp. 7617-7634 . https://doi.org/10.1002/chem.201000454
Publication
Chemistry - A European Journal
Status
Peer reviewed
ISSN
0947-6539Type
Journal article
Description
This work is funded by the EPSRC UKCollections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.