The compound (RCp)2TiS4(PAn)2 (1; RCp = η5-RC5H4, R = H, Me; An = 4-MeOC6H4) reacts with 1 or 2 equiv of oxygen to give the six- and seven-membered heterocycles (RCp)2TiOS4(PAn)2 (2) and (RCp)2TiO2S4(PAn)2 (3). These reactions appear to involve the dissociation of 1 to give (RCp)2TiS3(PAn) and [AnPS]3, followed by the oxygenation of the latter to give [AnPSO]n and insertion of an AnPSO fragment into (RCp)2TiS3(PAn) to give 2. In a similar way (RCp)2TiS3(PAn) adds [AnPS2]2 to give (RCp)2TiS5(PAn)2 (4), an all-sulfur analogue of 2. Compound 4 converts organic carbonyls into thiocarbonyls concomitant with the formation of 2. The structure of 3 was determined by single-crystal X-ray diffraction. (CH3C5H4)2TiO2S 4(P(C6H4OCH3))2 crystallizes in the triclinic space group P1, with a = 9.458 (3) Å, b = 10.611 (3) Å, c = 15.975 (5) Å, α = 94.96 (2)°, β = 109.34 (2)°, and γ = 105.38 (2)°. With use of 7288 unique reflections with I > 3.00σ(I), the structure was solved by direct methods and refined to a final R = 0.037 and Rw = 0.048. The structure consists of a (MeCp)2Ti moiety incorporated into a seven-membered Ti-O-P(S,An)-S-S-P(An,S)-O ring (each phosphorus atom maintaining a terminal sulfide and an anisole group). The reaction of 1 or 4 with organic carbonyls gives (MeCp)2TiO2S3(PAn)2, which exists as cis and trans isomers.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry