Insights into the Intramolecular Donor Stabilisation of Organostannylene Palladium and Platinum Complexes: Syntheses, Structures and DFT Calculations

Abstract

The syntheses of the transition metal complexes cis-[(4-tBu-2,6-{P(O)(OiPr)2}2C6H2SnCl)2MX2] (1, M = Pd, X = Cl; 2, M = Pd, X = Br; 3, M = Pd, X = I; 4, M = Pt, X = Cl), cis-[{2,6-(Me2NCH2)2C6H3SnCl}2MX2] (5, M = Pd, X = I; 6, M = Pt, X = Cl), trans-[{2,6-(Me2NCH2)2C6H3SnI}2PtI2] (7) and trans-[(4-tBu-2,6-{P(O)(OiPr)2}2C6H2SnCl)PdI2]2 (8) are reported. Also reported is the serendipitous formation of the unprecedented complexes trans-[(4-tBu-2,6-{P(O)(OiPr)2}2C6H2SnCl)2Pt(SnCl3)2] (10) and [(4-tBu-2,6-{P(O)(OiPr)2}2C6H2SnCl)3Pt(SnCl3)2] (11). The compounds were characterised by elemental analyses, (1)H, (13)C, (31)P, (119)Sn and (195)Pt NMR spectroscopy, single-crystal X-ray diffraction analysis, UV/Vis spectroscopy and, in the cases of compounds 1, 3 and 4, also by Mössbauer spectroscopy. All the compounds show the tin atoms in a distorted trigonal-bipyramidal environment. The Mössbauer spectra suggest the tin atoms to be present in the oxidation state III. The kinetic lability of the complexes was studied by redistribution reactions between compounds 1 and 3 as well as between 1 and cis-[{2,6-(Me2 NCH2)2C6H3SnCl}2PdCl2]. DFT calculations provided insights into both the bonding situation of the compounds and the energy difference between the cis and trans isomers. The latter is influenced by the donor strength of the pincer-type ligands.

Surface chemistry of porphyrins and phthalocyanines

“…Within these concepts, the surface is considered as a ligand with an unusually large "cone angle" [796] of 1801. For comparison with complexes adsorbed on metal surfaces, metal-metal bonded complexes of the type [M 2 L x ] yÀ [19] or complexes with metal-containing ligands such as stannylene complexes [17,18,797] appear to be especially useful, because the competing trans-oriented ligand is (or binds through) a metal atom in these systems.…”

Rational Syntheses and Serendipity: Complexes [LSnPtCl2(SMe2)]2, [{LSnPtCl(SMe2)}2SnCl2], [(LSn)3(PtCl2)(PtClSnCl){LSn(Cl)OH}], and [O(SnCl)2(SnL)2] with L=MeN(CH2CMe2O)2

“…Like the relatedc ompounds RN(CH 2 CH 2 O) 2 SnM (R = Me, tBu, Me 2 NCH 2 CH 2 ,M eOCH 2 CH 2 ;M = lone pair,C r(CO) 5 ,W (CO) 5 ), [1][2][3][4] complex 2 forms a cis-configured dimer by means of intermolecular O!Sn coordinationt og ive four-membered Sn 2 O 2 rings with intracyclic SnÀOd istances that range between 2.065(3) (Sn(2)ÀO(31)) and 2.147(4) (Sn(1)ÀO(31)).T he Sn(1)ÀO (17) (16) and 143.228 (13), respectively,d eviat-ing considerably from the ideal value of 1808.T he Sn(1)ÀN (14) (2.324(4) )a nd Sn(2)ÀN(34) (2.286(4) )d istances are slightly different and comparable to those in 6·3CH 2 Cl 2 .The chlorido ligands at the square-planar platinum centers are cis. The Pt(1)À Cl(2) (2.3600(17) )a nd Pt(2)ÀCl(3) (2.3647(13) )d istances are longer as compared to the Pt(1)ÀCl(1) (2.3078(14) )a nd Pt(2)ÀCl(4) (2.3057 (17) )o nes reflecting as uperior trans effect of the tin(II) aminoalkoxide 1 over dimethylsulfide, Me 2 S.…”

“…The equatorial positions at Sn(1) are taken by O (11), O(17), and Pt(1), those at Sn(2) by O(31), O(37), and Pt (2). The distortion from the ideal geometry is especially expressed by the N(14)-Sn(1)-O(31)a nd N(34)-Sn(2)-O(11) angles of 141.75 (16) and 143.228 (13), respectively,d eviat-ing considerably from the ideal value of 1808.T he Sn(1)ÀN(14) (2.324(4) )a nd Sn(2)ÀN(34) (2.286(4) )d istances are slightly different and comparable to those in 6·3CH 2 Cl 2 .The chlorido ligands at the square-planar platinum centers are cis. The Pt(1)À Cl(2) (2.3600(17) )a nd Pt(2)ÀCl(3) (2.3647(13) )d istances are longer as compared to the Pt(1)ÀCl(1) (2.3078(14) )a nd Pt(2)ÀCl(4) (2.3057 (17) )o nes reflecting as uperior trans effect of the tin(II) aminoalkoxide 1 over dimethylsulfide, Me 2 S.…”

“…[7] More recently,w ed emonstrated the intramolecularly coordinatedheteroleptic organostannylenes RSnCl( R = 2,6-(Me 2 NCH 2 ) 2 C 6 H 3 ,4 -tBu-2,6-[P(O)(O-iPr) 2 ] 2 C 6 H 2 ) react towards PtCl 2 as a s-donor ligand rather than under insertion into the PtÀCl bond. [16] Herein, we report the tin(II) amino alcoholate 1 behaving to-wardsP t II salts eithera saneutral donor ligand, inserting into PtÀCl bonds,o rt aking parti nr earrangement reactions giving products that range from the heterobimetallic complex [LSnPtCl 2 (SMe 2 )] 2 via the complex [{LSnPtCl(SMe 2 )} 2 SnCl 2 )] containing aP t ÀSnCl 2 ÀPt moiety to the heptanuclear cluster [(LSn) 3 (PtCl 2 )(PtClSnCl){LSn(Cl)OH}].T he novel compounds are characterized by standard analytical methodsa nd state-of-theart theoretical calculations including charge-decomposition analyses accompanying the experimental work. These studies contributet oaf urther understanding of the nature of the PtÀ Sn bond and help in answering the question as to whether this bond should be interpreted as ad ative bond or an electron-sharing bond with formulations, such as Sn II !Pt II ,S n III -Pt I , or Sn IV !…”

Anorganische Chemie 2013

“…Dies zeigte die Bildung der 2:1‐Komplexe RSn(Cl)MX2Sn(Cl)R (M = Pd, Pt) mit Palladium(II)‐ und Platin(II)halogeniden. In die Platin‐Chlorbindungen kann SnCl2 einschieben, sodass sich RSn(Cl)M (SnCl3)2Sn(Cl)R bildet 76. Aus triethylphosphinstabilisierten, bis(silylierten) Stannylenen [R'Si(SiMe3)2]Sn·PMe3 entstehen als Folge einer 1,2‐Trimethylsilylgruppenmigration in der Koordinationssphäre der Übergangsmetalle die Palladium(0)‐ und Platin(0)komplexe der resultierenden Silastannene.…”