Activation of dithioformate by iron complexes: insertion of alkynes into the coordinated CS bond. X-ray structures of Fe[η3-HB(H)2←SC(SMe)H](CO)(PMe3)2 and Fe[η3-SC(Ph)CHCH(SMe)](CO)(PMe3)2

✍ Scribed by Dilip V. Khasnis; Nadine Pirio; Daniel Touchard; Loïc Toupet; Pierre H. Dixneuf

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 896 KB
• Volume: 198-200
• Category: Article
• ISSN: 0020-1693
• DOI: 10.1016/s0020-1693(00)92361-2

✦ Synopsis

BH, containing iron complexes Fe(q'-HB(H),SCHSR')(CO)(PR,), (3) were prepared by reduction of Fe(q'-CS,R')(X)(CO)(PR& derivatives (2) with NaBH,. The X-ray structure of 3a (R' = R = Me) shows the cis addition of the H-and BH, fragments to the coordinated dithioformate C-S bond and that one B-H bond is coordinated to the iron atom. The removal of BH3 from 3, on treatment with pyridine, generates a 16-electron iron moiety which can trap two-electron ligands (CO, PRJ or react with alkynes HC= C-R (R=Ph, H, C(Me)=CH,) to give the insertion of the alkyne into the dithioformate coordinated C-S bond and Fe(T3-S-C(R)=CH-CH-SMe)(CO)(PR,>, complexes. The latter are stable for R=Ph (6), for which the structure has been determined by X-ray diffraction, and R=H (8); the cleavage of their Fe-CH bond leads to new sulfurcontaining metallacycles 7 (R=Ph) and 10 (R= CMe=CH,).