Stephen B. Falloon

Cluster-assisted cyclooligomerization of thietane. A new route to polythioether macrocycles

Abstract The trirhenium complex Re 3 (CO) 10 [μ- SCH 2 CH 2 CH 2 ](μ-H) 3 ( 1 ) was found to produce an oligomerization of thietane at 25° C over 18 h to yield the new complex Re 3 (CO) 10 [μ-SCH 2 CH 2 CH 2 SCH 2 CH 2 -CH 2 SCH 2 CH 2 CH 2 SCH 2 CH 2 CH 2 ](μ-H) 3 ( 2 ), in 47% yield. Details of the structure of compound 2 were obtained rom a single crystal X-ray diffraction analysis of its PMe 2 Ph derivative 3 . It was found to contain a bridging thiolate group SCH 2 CH 2 CH 2 that is terminated with a SCH 2 CH 2 CH 2 SCH 2 CH 2 CH 2 SCH 2 CH 2 CH 2 macrocycle. The macrocycle was cleaved from the cluster by treatment with NaOEt and the free molecule trithiacyclodecane was isolated in 32% yield. Crystal data for 3 : space group = P 2 1 / n , a = 8.637(2) A, b = 41.80(1) A, c = 15.418(2) A, β = 111.79 (2)°, Z = 4, 2836 reflections, R = 0.036.

Methods for attaching metal-capped sp carbon chains to metalclusters: synthesis, structure and reactivity of rhenium–triosmiumcarbon complexes[(η5-C5Me5)Re(NO)(PPh3)(CC)nOs3(CO)10H]

Reactions of [(η 5 -C 5 Me 5 )Re(NO)(PPh 3 ) {(CC) n H}] and [Os 3 (CO) 10 (NCMe) 2 ] give the title Re(CC) n Os 3 complexes (n = 1–3, 83–61%); a crystal structure (n = 1), and IR and NMR properties, indicate contributions by neutral Re–(CC) n –(Os 3 ) and zwitterionic + Re(CC) n (Os 3 ) - resonance forms.