The structure of bis-(3,5-dimethyl-1,2-dithiolium) tetrachloroferrate(II): a comparison of structural details derived from two independent diffractometer analyses

Abstract

We wish to thank Dr E. R. Clark of the Pharmacology Department of Leeds University for valuable discussions, Mr D. Akrigg for technical assistance and the Leeds University Computing Laboratory for the provision of computing facilities.Note added in proof:-The structure of TM1 has been congrmed as TTTT. The structure of ome TM1 has recently been determined as TTGT (manuscripts in preparntion).References CHOTHIA, C. t~ PAULING, P. (1969) Results from two independent X-ray diffraction studies are discussed. Both analyses are based on threedimensional diffractometer data with least-squares refinement of the scattering model. In other details the experimental and refinement techniques employed are substantially different. The mean difference between corresponding parameters derived from the two analyses is ca.

A Practical Synthesis of Thiopyrylium Tetrafluoroborate from Ethyl Vinyl Sulfide

“…The C−S bond lengths in 4d of 163.7(3) and 166.4(3) pm are shorter than in the 4‐( p ‐dimethylaminophenyl)‐2,6‐diphenyl thiopyrylium cation (171 and 172 pm),16 and also shorter than in thiophene (171.4 pm) 17. They are quite similar to the related 1,3‐dithiolium ion (167.6 and 168.1 pm)18 and the 3,5‐dimethyl‐1,2‐dithiolium ion (166.7 and 169.6 pm) 19. C−S single bonds such as those in (CH 3 ) 2 S (180.2 pm)20 and a 1,3‐dithiol (182 pm) are longer,18 whilst C−S double bonds such as those in H 2 C=S (161.1 pm)21 and CH 2 =SF 4 (155.4 pm)22 and triple bonds as in CF 3 −C≡SF 3 (142 pm)23 are markedly shorter.…”