Tuning the sulfur–heterometal interaction in organolead(IV) complexes of [Pt2(μ-S)2(PPh3)4]

Abstract

Reactions of [Pt 2 (l-S) 2 (PPh 3 ) 4 ] with Ph 3 PbCl, Ph 2 PbI 2 , Ph 2 PbBr 2 and Me 3 PbOAc result in the formation of bright yellow to orange solutions containing the cations [Pt 2 (l-S) 2 (PPh 3 ) 4 PbR 3 ] + (R 3 = Ph 3 , Ph 2 I, Ph 2 Br, Me 3 ) isolated as PF 6 À or BPh 4 À salts. In the case of the Me 3 Pb and Et 3 Pb systems, a prolonged reaction time results in formation of the alkylated species [Pt 2 (l-S)(l-SR)(PPh 3 ) 4 ] + (R = Me, Et). X-ray structure determinations on [Pt 2 (l-S) 2 (PPh 3 ) 4 PbMe 3 ]PF 6 and [Pt 2 (l-S) 2 (PPh 3 ) 4 PbPh 2 I]PF 6 have been carried out, revealing different coordination modes. In the Me 3 Pb complex, the (four-coordinate) lead atom binds to a single sulfur atom, while in the Ph 2 PbI adduct coordination of both sulfurs results in a five-coordinate lead centre. These differences are related to the electron density on the lead centre, and indicate that the interaction of the heterometal centre with the {Pt 2 S 2 } metalloligand core can be tuned by variation of the heteroatom substituents. The species [Pt 2 (l-S) 2 (PPh 3 ) 4 PbR 3 ] + display differing fragmentation pathways in their ESI mass spectra, following initial loss of PPh 3 in all cases; for R = Ph, loss of PbPh 2 occurs, yielding [Pt 2 (l-S) 2 (PPh 3 ) 3 Ph] + , while for R = Me, reductive elimination of ethane gives [Pt 2 (l-S) 2 (PPh 3 ) 3 PbMe] + , which is followed by loss of CH 4 .

Structural analysis of organometallic compounds with soft ionization mass spectrometry

“…Ag (Rais et al, 2002) As (Pedersen & Francesconi, 2000) Au (Dinger & Henderson, 1998a, b;Dinger et al, 1998;Dinger & Henderson, 1999;Goss et al, 2003;Kilpin et al, 2007) Cu (Lipshutz et al, 1999) Fe (Alley & Henderson, 2001;Henderson & Alley, 2002) Hg (Nicholson & Whitley, 2004) Ir (Ozkar & Finke, 2004) Pb (Mester & Pawliszyn, 1999;Pham et al, 2007) Pd (Chevrin et al, 2007;Moreno-Manas et al, 2003;Pla-Quintana & Roglans, 2005) Pt (Mastrorilli et al, 2004) Re (Jiang et al, 2000) Ru (Wang et al, 2002;Yeo et al, 1999) Sb (Brown et al, 2006) Sn (Beckmann et al, 2002;Henderson & Taylor, 1996;Lawson et al, 1996;Yeo et al, 2001) Te (Beckmann et al, 2005) ESI QqQ…”

“…Fe (Osei-Twum et al, 2005) Ag (Rais et al, 2002); As (Larsen et al, 2001); Au (Dinger et al, 1998); Bi (Dostál et al, 2007c;Fridrichová et al, 2009); Cr (Moret et al, 2005); Ga (Young et al, 2007); Ir (Ogo et al, 1999); Pb (Mester & Pawliszyn, 1999;Pham et al, 2007); Pd (Macchioni et al, 2003); Pt (Hartnell & Arnold, 2004;Mastrorilli et al, 2004); Rh (Dorcier et al, 2008;Jimenez et al, 2008); Rh and Sb (Brown et al, 2006); Ru (Dorcier et al, 2005;Dorcier et al, 2008;Yeo et al, 1999); Ru and Fe (Paim et al, 2005); Os (Dorcier et al, 2005;Dorcier et al, 2008); Sb (Dostál et al, 2007c;Fridrichová et al, 2009); Sn (Holčapek et al, 2006;Kašná et al, 2008); V (Palačková et al, 2007;Vinklárek et al, 2006); heteromultimetallic (Packheiser & Lang, 2007;Packheiser et al, 2008a;Packheiser et al, 2008b) [M+H] +…”

“…The important point is the development of appropriate chromatographic methods. Gas chromatography combined with inductively coupled plasma time-of-flight mass spectrometry (ICP-MS) enables high sensitivity and resolution, but the time-consuming preparation of volatile derivates is inevitable, and can influence the reproducibility, especially for methyl (Larsen et al, 2001;Mester & Pawliszyn, 1999) 16 CH 4 methyl (Chalupa et al, 2006;Larsen et al, 2001;Pham et al, 2007) 18 H 2 O hydroxyl, carboxylate (Baul et al, 2006d;Baul et al, 2007b;Florencio et al, 1997;Chalupa et al, 2006;Chalupa et al, 2008;Jirásko et al, 2009;Kolářová et al, 2004;Larsen et al, 2001; 28 C 2 H 4 ethyl (Kolářová et al, 2004;Lamb & Sweetman, 1996) CO carbonyl (Baul et al, 2005a;Jirásko et al, 2007;Seiwert & Karst, 2007;Yeo et al, 1999) CO carbene complexes (Crawford et al, 2006;Jiang et al, 2000;KaneMaguire et al, 1996;Martinez-Alvarez et al, 2004;Mastrorilli et al, 2004;Mlýnek & Dahl, 1997;Moret et al, 2005;Thompson et al, 2003) N 2 azo group (Baul et al, 2005b;Baul et al, 2006b) 29 C 2 H 5 .…”

Further investigations on the methylation chemistry of [Pt2(µ-S)2(PPh3)4]

“…The use of other methyl halides is also not convenient since MeCl and MeBr are gases under ambient conditions. Me 3 PbO 2 CCH 3 has been shown to convert [Pt 2 (m-S) 2 (PPh 3 ) 4 ] to [Pt 2 (m-S) (m-SMe)(PPh 3 ) 4 ] þ [10], but the high toxicity of organolead compounds makes this…”

Thallium(III) complexes of the metalloligands [Pt2(μ-S)2(PPh3)4] and [Pt2(μ-Se)2(PPh3)4]

“…[15,16,17] With the exception of the very hardest metals, 1 acts as a very general metalloligand towards a diverse range of metal centres. [18] While a number of complexes of [Pt 2 (-S) 2 (PPh 3 ) 4 ] with main group metal centres are known [19], such as lead [20], indium and gallium [21] and bismuth [22,23,24], organometallic derivatives are limited to organo-tin [25] and organo-lead [26] compounds. In this paper we report our studies on thallium(III) derivatives, including organometallics.…”