Access to Central Carbon Chirality through Cycloplatination of 1-(2-Pyridinylthio)propanone by cis-[PtCl₂(S-SOMe(p-tolyl))]. The Crystal Structure of (S_sS_c)-[Pt{py{SCHC(O)Me}-2}Cl(SOMe(p-tolyl))]

Abstract

Cycloplatination of the prochiral sp 3 C-H bond of 1-(2-pyridinylthio)propanone (py{SCH 2 C-(O)Me}-2, 1a) by cis-[PtCl 2 (SOMe 2 )] in dry ethanol affords [Pt{py{SCHC(O)Me}-2}Cl(SOMe 2 )] (3a) in 77% isolated yield without any side product. The same reaction using the chiral complex cis-[PtCl 2 (S-SOMe(p-tolyl))] (the absolute configuration of sulfur is indicated for the coordinated ligand) leads to two cycloplatinated diastereoisomers, 4a (S s R c ) and 4b (S s S c ), in 12.9 and 33.7% yield, respectively (de 44.6%). Their absolute configuration was deduced from the analysis of the 1 H NMR spectra and confirmed by an X-ray structural investigation of 4b. Diastereomer 4b was shown to react with PPh 3 to give the enantiomer [Pt{py{SCHC-(O)Me}-2}Cl(PPh 3 )] with the central carbon chirality only. Rather surprisingly, attempted cycloplatination of py{SCH 2 C(O)Ph}-2 (1b) by cis-[PtCl 2 (SOMe 2 )] affords the cycloplatinated complex [Pt{py{SCHC(O)Ph}-2}Cl(SOMe 2 )] (3b) in a miserable yield.

N-Assisted CPh–H Activation in 3,8-Dinitro-6-phenylphenanthridine. New C,N-Cyclometalated Compounds of Platinum(II): Synthesis, Structure, and Luminescence Studies

“…The 3,8-dinitro-6-phenylphenanthridine is not planar, with the phenyl ring forming an angle of 62.45(13)° ( 1A ) [64.36(11)° ( 1B )] with the phenanthridine fragment. The phenyl group is not orientated to the Pt atom, which rejects a Pt(1)···H(1) or Pt(2)···H(24) interaction in the solid state, as observed in many examples described in the literature. , …”

“…The phenyl group is not orientated to the Pt atom, which rejects a Pt(1)•••H(1) or Pt(2)•••H(24) interaction in the solid state, as observed in many examples described in the literature. 48,49 Synthesis and Characterization of [{Pt(μ-Cl)(C ∧ N)} 2 ] (2) (C ∧ N = 3,8-dinitro-6-phenylphenanthridine-H-κC,N). When a suspension of 1•0.5 Me 2 CO in 2-methoxyethanol was refluxed for 2 h, it turned into a dark brownish mixture, from which compound 2 was isolated as an air-stable solid although unpurified with a dark gray and very insoluble byproduct, likely Pt(0).…”

Structural and Mechanistic Look at the Orthoplatination of Aryl Oximes by Dichlorobis(sulfoxide or sulfide)platinum(II) Complexes

“…All (5) 1.387(4) C(1-6)avg 1.399 (12) 1.383 (7) 1.384 (7) 1.392(7) C(6)-C (7) 1.450 (12) 1.451 (7) 1.464 (6) 1.473(5) C(7)-C (8) 1.494 (12) 1.487 (6) 1.483 (6) 1.484 (6) bond angle 3b 3c1 3c2 3e exhibited a distinct planar geometry making intermolecular interactions feasible; this was indeed established for 3b and 3c. Small bite angles of ca.…”

Easy access to diastereomerically pure platinacycles

“…The synthesis and study of the potential applications of cycloplatinated compounds have attracted great interest in recent years. [1][2][3][4] Most of the articles published so far are focused on complexes having a s(Pt-Csp 2 , aryl), or to a lesser extent a s(Pt-Csp 3 ) bond. Platinacycles with a s(Pt-Csp 2 , ferrocene) bond are not common.…”