Abstract
The complexes M(PCy3)2(CO)3 (M = Cr, Mo, W) react with phenyl disulfide to form stable 17-electron radical complexes .M(PCy3)2(CO)3(SPh). Reaction with other alkyl and aryl disulfides also yields stable radicals and reaction with I2 yields .W(PiPr3)2(CO)3(I). Reaction with thiols, hydrogen sulfide and hydrogen iodide yield the corresponding 18-electron hydrides W(PiPr3)2(CO)3(H)(X). The crystal structure of W(PiPr3)2(CO)3(H)(I) is reported and allows comparison with the structure of the radical complex .W(PiPr3)2(CO)3(I). The W-H bond strengths in these heteroatom complexes are low, 55-57 kcal mol-1. In spite of steric crowding, H atom transfer from W(PiPr3)2(CO)3(H)(SPh) to .Cr(CO)2(PPh3)Cp occurs readily due to the stronger nature of the Cr-H bond formed. The chromium radical does not appear to attack the molecular hydrogen complex W(Pr3)2(CO)3(H2) or its dihydride form W(Pr3)2(CO)3(H)2 based on rate of hydrogenation studies. Phenyl disulfide does react with either W(Pr3)2(CO)3(H2) or its dihydride tautomer W(Pr3)2(CO)3(H)2 to form thiophenol and W(Pr3)2(CO)3(SPh.). This reaction is proposed to proceed by reaction of .SPh radicals which are generated in situ. These studies are used to bracket the first W-H bond dissociation energy in W(Pr3)2(CO)3(H)2. Additional studies of H atom and heteoratom transfer are described.
| Original language | English |
|---|---|
| Pages (from-to) | 317-327 |
| Number of pages | 11 |
| Journal | Inorganica Chimica Acta |
| Volume | 259 |
| Issue number | 1-2 |
| State | Published - Jun 1 1997 |
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Keywords
- Chromium complexes
- Hydrogen sulfide complexes
- Molybdenum complexes
- Thiol complexes
- Tungsten complexes
ASJC Scopus subject areas
- Biochemistry
- Inorganic Chemistry
- Physical and Theoretical Chemistry
- Materials Chemistry
Cite this
Reactions of the complexes M(Pr3)2(CO)3(M = Cr, Mo, W; R = iPr, Cy) with thiols, hydrogen sulfide, disulfides, hydrogen iodide and iodine. The role of heteroatoms in determining the metal-hydrogen bond strength at a sterically crowded metal center. / Lang, Russel F.; Ju, Telvin D.; Kiss, Gabor; Hoff, Carl; Bryan, Jeffrey C.; Kubas, Gregory J.
In: Inorganica Chimica Acta, Vol. 259, No. 1-2, 01.06.1997, p. 317-327.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Reactions of the complexes M(Pr3)2(CO)3(M = Cr, Mo, W; R = iPr, Cy) with thiols, hydrogen sulfide, disulfides, hydrogen iodide and iodine. The role of heteroatoms in determining the metal-hydrogen bond strength at a sterically crowded metal center
AU - Lang, Russel F.
AU - Ju, Telvin D.
AU - Kiss, Gabor
AU - Hoff, Carl
AU - Bryan, Jeffrey C.
AU - Kubas, Gregory J.
PY - 1997/6/1
Y1 - 1997/6/1
N2 - The complexes M(PCy3)2(CO)3 (M = Cr, Mo, W) react with phenyl disulfide to form stable 17-electron radical complexes .M(PCy3)2(CO)3(SPh). Reaction with other alkyl and aryl disulfides also yields stable radicals and reaction with I2 yields .W(PiPr3)2(CO)3(I). Reaction with thiols, hydrogen sulfide and hydrogen iodide yield the corresponding 18-electron hydrides W(PiPr3)2(CO)3(H)(X). The crystal structure of W(PiPr3)2(CO)3(H)(I) is reported and allows comparison with the structure of the radical complex .W(PiPr3)2(CO)3(I). The W-H bond strengths in these heteroatom complexes are low, 55-57 kcal mol-1. In spite of steric crowding, H atom transfer from W(PiPr3)2(CO)3(H)(SPh) to .Cr(CO)2(PPh3)Cp occurs readily due to the stronger nature of the Cr-H bond formed. The chromium radical does not appear to attack the molecular hydrogen complex W(Pr3)2(CO)3(H2) or its dihydride form W(Pr3)2(CO)3(H)2 based on rate of hydrogenation studies. Phenyl disulfide does react with either W(Pr3)2(CO)3(H2) or its dihydride tautomer W(Pr3)2(CO)3(H)2 to form thiophenol and W(Pr3)2(CO)3(SPh.). This reaction is proposed to proceed by reaction of .SPh radicals which are generated in situ. These studies are used to bracket the first W-H bond dissociation energy in W(Pr3)2(CO)3(H)2. Additional studies of H atom and heteoratom transfer are described.
AB - The complexes M(PCy3)2(CO)3 (M = Cr, Mo, W) react with phenyl disulfide to form stable 17-electron radical complexes .M(PCy3)2(CO)3(SPh). Reaction with other alkyl and aryl disulfides also yields stable radicals and reaction with I2 yields .W(PiPr3)2(CO)3(I). Reaction with thiols, hydrogen sulfide and hydrogen iodide yield the corresponding 18-electron hydrides W(PiPr3)2(CO)3(H)(X). The crystal structure of W(PiPr3)2(CO)3(H)(I) is reported and allows comparison with the structure of the radical complex .W(PiPr3)2(CO)3(I). The W-H bond strengths in these heteroatom complexes are low, 55-57 kcal mol-1. In spite of steric crowding, H atom transfer from W(PiPr3)2(CO)3(H)(SPh) to .Cr(CO)2(PPh3)Cp occurs readily due to the stronger nature of the Cr-H bond formed. The chromium radical does not appear to attack the molecular hydrogen complex W(Pr3)2(CO)3(H2) or its dihydride form W(Pr3)2(CO)3(H)2 based on rate of hydrogenation studies. Phenyl disulfide does react with either W(Pr3)2(CO)3(H2) or its dihydride tautomer W(Pr3)2(CO)3(H)2 to form thiophenol and W(Pr3)2(CO)3(SPh.). This reaction is proposed to proceed by reaction of .SPh radicals which are generated in situ. These studies are used to bracket the first W-H bond dissociation energy in W(Pr3)2(CO)3(H)2. Additional studies of H atom and heteoratom transfer are described.
KW - Chromium complexes
KW - Hydrogen sulfide complexes
KW - Molybdenum complexes
KW - Thiol complexes
KW - Tungsten complexes
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UR - http://www.scopus.com/inward/citedby.url?scp=0001188967&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0001188967
VL - 259
SP - 317
EP - 327
JO - Inorganica Chimica Acta
JF - Inorganica Chimica Acta
SN - 0020-1693
IS - 1-2
ER -