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The new compounds Re2(CO)9(SCH2CHMeCH2) (2) and W(CO)5(SCH2CHMeCH2), 8, have been prepared by the reactions of Re2(CO)9(NCMe) (1) and W(CO)5(NCMe) (7) with 3-methylthietane, (SCH2CHMeCH2, 3-MT). Compounds 1, 2, 7, and 8 have been found to react with SCH2CHMeCH2 at reflux to yield substantial amounts of the polythioether macrocycle 3,7,11-trimethyl-1,5,9-trithiacyclododecane (Me312S3) by a macrocyclization process consisting of a metal-induced ring-opening cyclooligomerization of three molecules of 3-MT. Me312S3 is formed as two isomers, cis,trans,trans-3,7,11-trimethyl-1,5,9-trithiacyclododecane (c,t,t-Me312S3, 3) and cis,cis,cis-3,7,11-trimethyl-1,5,9-trithiacyclododecane (c,c,c-Me312S3, 4), due to different orientations of the methyl substituents in the ring. Small amounts of higher macrocycles with the general formula (SCH2CHMeCH2) n (n > 3) are also formed, but these could not be isolated in pure forms. A comparison of the two catalysts shows that the rhenium catalyst exhibits a higher activity and higher selectivity for the formation of Me312S3 than the tungsten complex. The reactions of 1 with 3 and 4 have yielded the new compounds Re2(CO)9(c,t,t-SCH2CHMe(CH2SCH2CHMe)2CH2) (5) and Re2(CO)9(c,c,cSCH2CHMe(CH2SCH2CHMe)2CH2) (6), respectively. The molecular structures of the free molecule 3 and the complexes 5 and 6 were established by single-crystal X-ray diffraction analyses.

The reaction of Re2(CO)9(NCMe), 1, with 3,3-dimethylthietane (SCH2CMe2CH2, 3,3-DMT) yielded the complex Re2(CO)9(SCH2CMe2CH2), 2. Compound 2 has been found to react with 3,3-DMT at 100 °C to yield the polythioether macrocycles 3,3,7,7,11,11-hexamethyl-1,5,9-trithiacyclododecane, 3 (Me612S3), 3,3,7,7,11,11,15,15-octamethyl-1,5,9,13-tetrathiacyclohexadecane, 4 (Me816S4), and 3,3,7,7,11,11,15,15,19,19-decamethyl-1,5,9,13,17-pentathiacycloeicosane, 5 (Me1020S5), catalytically, but the activity and yields of the macrocycles are low. High molecular weight oligomers of 3,3-DMT are the principal products. A macrocyclization mechanism consisting of a metal-induced ring-opening cyclooligomerization of three, four, and five molecules of 3,3-DMT, respectively, is proposed. The reaction of 3 with CpMn(CO)3 in the presence of UV irradiation yielded the complex CpMn(CO)2(η1-Me612S3), 6. The molecular structures of each of the macrocycles 3, 4, and 5 and the complexes 2 and 6 were determined by single-crystal X-ray diffraction analyses.

Die Cyclotriphosphane (PtBu)3 und (PiPr)3 reagieren mit [Fe2(CO)9] unter Bildung der Zweikernkomplexe [Fe2(CO)6(PR)6] (R = tBu: 1; iPr: 2). 2 entsteht auch bei der Reaktion von [Fe(CO)5] mit (PiPr)3 neben dem Komplex [Fe2(CO)4(PiPr)6] (3). Aus der Reaktion von PiPr(PtBu)2 und PiPrCl2 mit [Fe2(CO)9] kann weiterhin [Fe2(CO)3Cl2(PtBu)5] (4) isoliert werden. Die Umsetzungen von (PiPr)3 mit [Co2(CO)8] und [Ni(CO)4] führen zu den vier‐ und fünfkernigen Clustern [Co4(CO)10(PiPr)3] (5), [Ni4(CO)10(PiPr)6] [2] und [Ni5(CO)10(PiPr)6] (6). Weiterhin kann aus der Reaktion von [Ir(C8H12)Cl]2 mit K2(PPh)4 der Komplex [Ir4(C8H12)4Cl2(PPh)4] (7) erhalten werden. Die Strukturen von 1–7 konnten durch Einkristall‐Röntgenstrukturanalyse aufgeklärt werden (1: Raumgruppe P21/c (Nr. 14), Z = 8, a = 1 758,8(16) pm, b = 3 625,6(18) pm, c = 1 202,7(7) pm, β = 90,07(3)°; 2: Raumgruppe P1 (Nr. 2), Z = 1, a = 880,0(2) pm, b = 932,3(3) pm, c = 1 073,7(2) pm, α = 79,07(2)°, β = 86,93(2)°, γ = 72,23(2)°; 3: Raumgruppe Pbca (Nr. 61), Z = 8, a = 952,6(8) pm, b = 1 787,6(12) pm, c = 3 697,2(30) pm; 4: Raumgruppe P21/n (Nr. 14), Z = 4, a = 968,0(4) pm, b = 3 362,5(15) pm, c = 1 051,6(3) pm, β = 109,71(2)°; 5: Raumgruppe P21/n (Nr. 14), Z = 4, a = 1 040,7(5) pm, b = 1 686,0(5) pm, c = 1 567,7(9) pm, β = 93,88(4)°; 6: Raumgruppe Pbca (Nr. 61), Z = 8, a = 1 904,1(8) pm, b = 1 959,9(8) pm, c = 2 309,7(9) pm. 7: Raumgruppe P1 (Nr. 2), Z = 2, a = 1 374,4(7) pm, b = 1 476,0(8) pm, c = 1 653,2(9) pm, α = 83,87(4)°, β = 88,76(4)°, γ = 88,28(4)°).