Wolfgang Weigand

Synthesis and coordination properties of amphiphilic 3-oxodithiocarboxylic esters ☆

Abstract The amphiphilic 3-oxodithiocarboxylic esters 2a-d have been prepared starting from p -hydroxy acetophenone. These esters react with transition metal salt MX 2 (M  Mn, Fe, Co, Ni, Pd, Pt, Cu, Zn; X  Cl, OAc) to yield the tetrahedral and cis configurated square planar chelate complexes M(II) [SC(SR 2 )CHC(O)C 6 H 4 - p -OR 1 ] 2 (R 1 = C 6 H 13 ,C 12 H 25 ; R 2 = CH 3 ,C 6 H 13 ,C 12 H 25 ) ( 3a-e, 5a-f, 6a-c ) as well as the octahedral complexes py 2 M(II) [SC(SCH 3 )CHC(O)C 6 H 4 - p -OC 6 H 13 ] 2 (M = Mn, Fe) ( 4a,b ) and fac -Co(III) [SC(SR 2 )CHC(O)C 6 H 4 - p -OC 6 H 13 ] 3 (R 2 = CH 3 , C 6 H 13 ) ( 7 and 8 ), respectively. The structures of 5c and 8 have been determined by single-crystal X-ray diffraction.

OXIDATIVE ADDITION OF 2,3,4-BENZOTRITHIEPIN 1-OXIDE TO PLATINUM(0) COMPOUNDS : A CONVENIENT SYNTHETIC ROUTE TO PLATINUM(II) THIOSULFINATO COMPLEXES

Abstract The oxidative addition of 2,3,4-trithiepin 1-oxide 2 to (Ph3P)2Pt(C2H4) 5 gives the platinum(II) thiolato thiosulfinato complex cis-{(Ph3P)2PtS-S(O)-CH2-C6H4-CH2-S6. The structure of 2 was established by X-ray structural analysis. 2 crystallizes in the monoclinic space group P21/c with a = 878.52(10), b = 1263.4(2), c = 936.95(10) pm, β = 117.818(9)°, Z = 4. The 2,3,4-trithiepin 2-oxide 4 reacts with 5 to form the diplatinum(II) thiolato complex 8. Formally, 1 equiv. SO has been eliminated during this reaction.

Chemie der isoblausäure: IV. additionen von CNH-komplexen des chroms, wolframs und eisens an heteroallen

Abstract “In situ” generated hydrogen isocyanide complexes are treated with cyclohexyl isocyanate and carbodiimides (PhNCNPh, CyNCNCy) to give metal-stabilized isocyano carboxamides ([M(CO) 5 {CNC(O)NHCy}] (M = Cr, W), [Fe(Cp)(diphos) {CNC(O)NHCy}]BF 4 ) and isocayno carboxamidines ([Fe(CN)(Cp)(CO)-{CNC(-NPh)NHPh}], [Fe(Cp)(CO){CNC(NCy)NHCy} 2 ]BF 4 , [Fe{CNC(NCy)NHCy} 2 (ophen) 2 ](BF 4 ) 2 ), respectively.

Pseudohalogeno-Metallverbindungen: LXX. Neue stabile Metallcyanid-Bortrifluorid Addukte; kristallstrukturanalyse von (η5-C5H5)(Ph3P)2Ru(CNBF3)☆

Abstract Adducts of the metal cyanides and borontrifluoride, (η5-C5H5L2MCNBF3 (M = Fe, Ru; L = PPh3, 1 2 Ph2PCH2CH2PPh2), (η5-C5H5)(OC)(Ph3P)FeCNBF3, (R3P)2Pt(CNBF3)2 (R = Et, Ph) are obtained after use of tetrafluoroboric acid Et2O or BF3·Et2O, respectively. The crystal structure of (η5-C5H5(Ph3P)2-RuCNBF3 has been determined (∢RuCN 174.6, ∢CNB 173.5°; Ru-C 1.95, C-N 1.15, N-B 1.56 A).

Enantiomeric separation of racemic thiosulphinate esters by high-performance liquid chromatography

Abstract High-performance liquid chromatographic methods using chiral stationary phases were developed for the separation of racemic mixtures of biologically active alk(en)ylsulphinothioic acid alk(en)yl esters (syn. thiosulphinate esters, ts) from natural (Allium cepa L.) or synthetic origin. Aromatic substituted thiosulfinate esters could be baseline resolved using helical (+)-poly(triphenylmethyl methacryalte)-coated silica gel [Chiralpak OT (+)] as chiral stationary phase and methanol as eluent. A correlation between chromatographic resolution and the structures of the thiosulphinate esters could be established. A preparative separation of diphenyl-ts was achieved with cellulose triacetate (CTA) as the stationary phase. The elution sequence of diphenyl-ts enantiomers on the CTA column is reversed when compared to that on the Chiralpak OT (+).

Pseudohalogenometallverbindungen: LXVI. Darstellung und struktur von trans-difulminato-bis(triphenylphosphan)platin(II), (Ph3P)2Pt(CNO)2☆

Abstract trans -(Ph 3 )P) 2 Pt(CNO) 2 has been prepared by oxidative addition of nitromethane to (η 2 -C 2 H 4 )Pt(PPh 3 ) 2 . Its crystal structure has been determined. The PtCNO groups are linear. The bond lengths are: PtC 197.5(6), CN 112.9(8), NO 127.0(8) pm.

Pseudohalogenometallverbindungen: LXVII. Reaktionen von komplexen Metallcyaniden trans-(R3P)2M(CN)2 (M = Pd, Pt; R = Et, Ph) mit 1,3-Dioxolenium-tetrafiuoroborat

The cyano complexes (R3P)2Pt(CN)2 (R = Et, Ph) und (Ph3P)2Pd(CN)2 react with the dioxolenium salt [O-CH2CH2O-CH]+ BF4− with ring opening to give the isocyanide complexe [(R3P)2M(CNCH2CH2OCHO)2]2+ (BF4−)2 and [(R3P)2M-(CN)(CNCH2CH2OCHO)]+BF4−, which contain the new ligand (2-isocyanoethanol)-formiate. The complexes have been characterized by analysis and from their IR and NMR spectra.