Thermal fragmentation of acyl thiolato complexes to reactive metal sulfido intermediates. Structure of Ru([eta][sup 6]-SC[sub 3]Me[sub 3]COMe)(PPh[sub 3])[sub 2]

Journal Article · Sun Jan 01 04:00:00 EST 1995 · Organometallics; (United States)

DOI:https://doi.org/10.1021/om00001a043· OSTI ID:6602400

Feng, Q; Krautscheid, H; Rauchfuss, T B; Skaugset, A E; Venturelli, A ^[1]

---

1. Univ. of Illinois, Urbana, IL (United States)

In this study we have examined the thermal fragmentation of acyl thiolate complexes of the type (ring)M(SC[sub 3]Me[sub 3]COMe). While the (cymene)Ru derivative only gave insoluble materials, the thermolysis of the corresponding osmium compound, (cymene)Os(SC[sub 3]Me[sub 3]COMe) (2), proved very informative. Here it was established that the tetramethylfuran is indeed released prior to formation of the free cymene. Furthermore, two intermediates were observed, the second of which was identified as (cymene)[sub 3]Os[sub 3]S[sub 2]. This species is more stable with respect to loss of cymene than the corresponding (cymene)[sub 3]Ru[sub 3]S[sub 2]. Attempts were made to intercept intermediates in these fragmentation processes by employing PPh[sub 3] as a trapping agent. For the Ru case, PPh[sub 3] completely changed the course of the reaction and no tetramethylfuran was generated. Instead we obtained the structurally unusual [eta][sup 6]-acyl thiolate complex (5). We propose that this unimolecular step involves the formation of ([eta][sup 4]-cymene)Ru([eta][sup 6]-SC[sub 3]Me[sub 3]COMe). The forward rate for this equilibration is far slower than the rate of isomerization of the acyl thiolate and far faster than that for the unassisted thermal decomposition of (cymene)Ru(SC[sub 3]MesCOMe). This result leads to a more global assessment of the reactivity of the acyl thiolates: the orientation of the carbonyl center determines the decomposition pathway. 21 refs., 7 figs., 1 tab.

• DOE Contract Number: FG02-90ER14146
• OSTI ID: 6602400
• Journal Information: Organometallics; (United States), Journal Name: Organometallics; (United States) Vol. 14:1; ISSN ORGND7; ISSN 0276-7333
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400800 -- Combustion
Pyrolysis
& High-Temperature Chemistry
CHEMICAL ANALYSIS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DATA
DECOMPOSITION
EXPERIMENTAL DATA
GRAVIMETRIC ANALYSIS
INFORMATION
KINETICS
MOLECULAR STRUCTURE
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
ORGANOMETALLIC COMPOUNDS
PYROLYSIS
QUANTITATIVE CHEMICAL ANALYSIS
REACTION KINETICS
REFRACTORY METAL COMPOUNDS
RUTHENIUM COMPOUNDS
STRUCTURAL CHEMICAL ANALYSIS
THERMAL ANALYSIS
THERMAL GRAVIMETRIC ANALYSIS
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENT COMPOUNDS