Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Synthesis and desulfurization of 2,5-dihydrothiophene transition-metal complexes: Models for the hydrodesulfurization (HDS) of thiophene

Journal Article · · Inorganic Chemistry; (United States)
DOI:https://doi.org/10.1021/ic00019a015· OSTI ID:6837032

Several S-coordinated 2,5-dihydrothiophene (2,5-DHT) transition-metal complexes were synthesized in order to determine whether or not this type of coordination promotes butadiene elimination from the 2,5-DHT ligand, a step proposed in a mechanism for the hydrodesulfurization (HDS) of thiophene. Thermal decomposition of W(CO)[sub 5](2,5-DHT) and Re[sub 2](CO)[sub 9](2,5-DHT) at 110C liberates butadiene and free 2,5-DHT (relative ratio 1:4). Uncoordinated 2,5-DHT itself does not decompose at 120C after 3 days. Thus, S-coordination of 2,5-DHT to these metal centers does promote the liberation of butadiene. Upon being heated at 180C, MCl[sub 2](2,5-DHT)[sub 2] (M = Pd, Pt) gives off mainly thiophene and free 2,5-DHT (1:1) with only a small amount of butadiene. Thus, depending on the complex either butadiene or thiophene may be evolved. The reaction of Ru[sub 3](CO)[sub 12] with 2,5-DHT forms the trinuclear ([mu][sub 2]-H)Ru[sub 3](CO)[sub 9]([mu][sub 3]-1-4-[eta][sup 4]-DHT), whose X-ray structure determination shows that the sulfur and olefin of the 2,5-DHT coordinate to two different ruthenium atoms but also C-H cleavage occurs at C(2) forming a C-Ru bond. The structure of an S-coordinated DHT complex [Cp(PMe[sub 3])[sub 2]Ru(2,5-DHT)](PF[sub 6]) is also reported.

OSTI ID:
6837032
Journal Information:
Inorganic Chemistry; (United States), Journal Name: Inorganic Chemistry; (United States) Vol. 30:19; ISSN 0020-1669; ISSN INOCAJ
Country of Publication:
United States
Language:
English