Homogeneous Catalytic Carbonylation of Nitroaromatics. 8. Kinetic and Mechanistic Studies of the Carbon-Nitrogen Bond and Product Forming Steps from Ru(Ph2PCH2CH2PPh2)(CO)2[C(O)OCH3]2: The Turnover Limiting Reactions in the Catalytic Cycle

Gargulak, Jerry D.; Gladfelter, Wayne L.

doi:10.1021/ja00088a015

Cited by 54 publications

(28 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the presence of methanol and CO, this complex affords Ru(dppe)(CO) 2 {C(O)OCH 3 } 2 [17] and aniline. The aniline then attacks the carbomethoxy complex generating an arylisocyanate molecule that is then trapped by excess aniline to generate a diarylurea [18]. Only at a later stage of the catalytic reaction the diarylurea reacts with methanol to afford a methyl arylcarbamate and one equivalent of aniline.…”

Section: Resultsmentioning

confidence: 99%

Investigation of the reactivity of palladium(0) complexes with nitroso compounds: relevance to the palladiumphenanthroline-catalysed carbonylation reactions of nitroarenes

Gallo¹,

Ragaini²,

Cenini³

et al. 1999

Journal of Organometallic Chemistry

View full text Add to dashboard Cite

The electron transfer reaction between palladium(0) complexes and RNO compounds afforded different palladium species depending on the aromatic or aliphatic nature of R. When R = Ph a paramagnetic palladium complex 1 was isolated, whereas if R=Bu t the palladium enolate complex 2 was the unexpected reaction product. Complex 1 reacted with methanol and CO to yield Pd(phen){C(O)OCH 3 } 2 3, which was characterised by single-crystal X-ray structure determination. Compound 3 is a probable intermediate in the reductive carbonylation reaction of organic nitro compounds catalysed by palladium complexes. Nitrobenzene is in fact carbonylated to PhNHCO 2 Me, by using 3 as a very efficient catalyst.

show abstract

Section: Resultsmentioning

confidence: 99%

Investigation of the reactivity of palladium(0) complexes with nitroso compounds: relevance to the palladiumphenanthroline-catalysed carbonylation reactions of nitroarenes

Gallo¹,

Ragaini²,

Cenini³

et al. 1999

Journal of Organometallic Chemistry

View full text Add to dashboard Cite

show abstract

“…[26,30,31] With a 25∶1 molar ratio of DMC to MDA, a temperature of 180 ℃, and 1 mol% Zn(OAc) 2 •2H 2 O, the desired dicarbamate was formed in 97% yield. Besides, aromatic amine substrates consistently gave high yields (up to 98%) with DMC or DEC using Zn 4 O(OAc) 6 as a catalyst, regardless of the electronic properties of the substituents or the ring substitution pattern. [32] The general mechanism for the methoxycarbonylation between DMC and diamines was proposed for the basic catalytic system (Scheme 3).…”

Section: Dmc As Carbonyl Sourcementioning

confidence: 96%

“…Generally, the reductive carbonylation of nitroaromatics and dinitroaromatics with CO could be catalyzed by transitional metal complexes (such as Pd, Pt, Ru, Rh, Ir, etc.) [3][4][5][6][7] and the only by-product was CO 2 (Eq. 5).…”

Section: Co As Carbonyl Sourcementioning

confidence: 99%

Important Green Chemistry and Catalysis: Non‐phosgene Syntheses of Isocyanates – Thermal Cracking Way

2017

View full text Add to dashboard Cite

Currently, industrial production of isocyanates, or diisocyanates in particular, has been exclusively based on phosgene processes. Phosgene is extremely toxic and large amounts of corrosive HCl are produced as a side product. In the view of environment protection and society safety, development of non-phosgene processes for isocyanates production will be highly desired, and this should be one of the most important missions for green chemistry and catalysis. In this review, efforts for development of non-phosgene method for syntheses of isocyanates, i.e., catalytic syntheses of N-substituted carbamates from nitro-or amino-compounds with CO, dimethyl carbonate (DMC), urea and even CO 2 etc. as carbonyl sources, then thermal cracking of N-substituted carbamates to afford corresponding isocyanates, are summarized, and a brief prospect for non-phosgene syntheses of isocyanates is also addressed.

show abstract

“…New 1 H NMR signals at 3.03 and 3.66 ppm of complex (4) are attributed to CH3 protons of C(O)OCH 3 groups and to the O-CH 3 protons of the bridging ligands respectively. 32,33 The rhodium content in each of the complexes was determined by refluxing them with concentrated hydrochloric acid or 1:1 HNO3 for 6 h and then estimating the metal concentration in the solution by atomic absorption spectrometry at wavelength 255.6 nm using air-acetylene flame.…”

Section: %) [Rh(p-s)(co)2] (5)mentioning

confidence: 99%

“…30,32 Visible amounts of N,N'-ditolylurea were noticed within 10 min at ambient temperature. The solution in the vial was analyzed using gas chromatography at an interval of 30 min for 3 h. No trace of carbamate could be detected at any stage of the reaction.…”

Section: Phnh2 + Co → Hconhph (4)mentioning

confidence: 99%

Catalytic Activity of Supported Rhodium(I) Complex for the Carbonylation of Nitrobenzene: Mechanism for Carbamate Formation

Kim¹,

Kim²,

Cheong³

et al. 2010

Bulletin of the Korean Chemical Society

View full text Add to dashboard Cite

The investigation of the catalytic activity of supported rhodium(I) complex [Rh(P-S)(CO)2] (P-S; polymer anchored salicylic acid) toward the reductive carbonylation of nitrobenzene in DMF medium has been reported. Use of basic cocatalysts in the reaction medium enhanced the percentage of more useful phenyl carbamates. Spectroscopic studies indicate that the reaction proceeds through a dimer species [Rh(HS)(CO)(C(O)OCH3)(µ-OCH3)]2 and phenyl isocyanate is formed as an intermediate. A plausible reaction mechanism based on the identification of reactive intermediates from the soluble rhodium variety has been proposed for the carbonylation process.

show abstract

Homogeneous Catalytic Carbonylation of Nitroaromatics. 8. Kinetic and Mechanistic Studies of the Carbon-Nitrogen Bond and Product Forming Steps from Ru(Ph2PCH2CH2PPh2)(CO)2[C(O)OCH3]2: The Turnover Limiting Reactions in the Catalytic Cycle

Cited by 54 publications

References 0 publications

Investigation of the reactivity of palladium(0) complexes with nitroso compounds: relevance to the palladiumphenanthroline-catalysed carbonylation reactions of nitroarenes

Investigation of the reactivity of palladium(0) complexes with nitroso compounds: relevance to the palladiumphenanthroline-catalysed carbonylation reactions of nitroarenes

Important Green Chemistry and Catalysis: Non‐phosgene Syntheses of Isocyanates – Thermal Cracking Way

Catalytic Activity of Supported Rhodium(I) Complex for the Carbonylation of Nitrobenzene: Mechanism for Carbamate Formation

Contact Info

Product

Resources

About