Acenaphtho[5, 6-cd]-1, 2-dichalcogenoles and their platinum complexes. (8th January 2015)

• Record Type: Journal Article
• Authors: Diamond, Louise M.; Knight, Fergus R.; Cordes, David B.; Ward, Andrew C.C.; Slawin, Alexandra M.Z.; Woollins, J. Derek
• Is Part Of: Polyhedron. Volume 85(2015)
• Page Start: 395
• Page End: 404
• Publication Date: 2015-01-08
• Subjects: Chalcogen -- Acenaphthylene -- Platinum -- X-ray structure -- Coordination complex; Chemistry, Inorganic -- Periodicals; Chimie inorganique -- Périodiques; Organometaalverbindingen; Anorganische chemie; 546.05
• DOI: 10.1016/j.poly.2014.08.046
• Languages: English
• ISSNs: 0277-5387

Abstract

Graphical abstract: Seven platinum bis phosphine complexes have been prepared from acenaphtho[5, 6- cd ]-1, 2-dichalcogenoles AcenapylE2 E = S, Se, following metathetical addition of the dilithium precursors to cis -[PtCl2 (PR3 )2 ] (R3 = Ph3, Ph2 Me, PhMe2, Me3 ). [Pt(5, 6-AcenapylS2 )(COD)] was also prepared in a similar manner from (1, 5-cyclooctadiene)platinum(II) dichloride. Abstract: A related series of bis (phosphine) platinum complexes1 –5 and6 –8 bearing dichalcogenate acenaphthylene ligands have been synthesised. The chalcogen–chalcogen bonds in the parent acenaphtho[5, 6- cd ]-1, 2-dichalcogenoles (AcenapylE2 ;L1 E = S, L2 E = Se; Acenapyl = acenaphthylene-5, 6-diyl) were reduced with two equivalents of lithium triethylborohydride to form the dilithio-species. Metathetical addition of the lithium dichalcogenate species to a suspension of the appropriate cis- dichloro bis (phosphine)platinum in THF resulted in the formation of platinum(II) complexes [Pt(5, 6-AcenapylE2 )(PR3 )2 ] (1 E = S, R3 = Ph3 ;2 E = S, R3 = Ph2 Me;3 E = S, R3 = PhMe2 ;4 E = S, R3 = Me3 ;6 E = Se, R3 = Ph3 ;7 E = Se, R3 = Ph2 Me;8 E = Se, R3 = PhMe2 ). The dilithio-species ofL1 andL2 were also reacted with (1, 5-cyclooctadiene)platinum(II) dichloride. This reaction was successful withL1 resulting in the formation of platinum complex [Pt(5, 6-AcenapylS2 )(COD)] (5 ). Complexes1 –3 and5 –8 have been fully characterised, principally by multinuclear magnetic resonance spectroscopy, IR and MS. Secondary isotopomer effects create complex satellite systems observed in both the 31 P{ 1 H} NMR and 77 Se NMR spectra of selenium complexes6 –8 . X-ray structures were determined forL1, 1, 3 and6 and analysed, where appropriate, by measuring the peri -distance, splay angle magnitude, peri -atom displacement, central naphthalene ring torsions and the geometry around the platinum centre. Platinum was found to adopt a distorted square-planar geometry in all three complexes. Complex1 was found to have the greatest molecular distortion of all three complexes, showing that changing the phosphine group and also the chalcogen has a noticeable effect. Comparisons were made between6 and our previously reported [Pt(NapSe2 )(PPh3 )2 ] and [Pt(AcenapSe2 )(PPh3 )2 ] complexes; the level of distortion was found to decrease as the backbone is altered from naphthalene to acenaphthylene.