Abstract A straightforward phosgene‐free synthesis of aromatic isocyanates and diisocyanates is disclosed. Theoretical investigations suggested that the insertion of carbon dioxide (CO 2 ) by dialkyltin(IV) dialkoxides could be used to convert aromatic amines into aromatic mono‐ and dicarbamates. Here we show, that methyl phenylcarbamate (MPC) from aniline using organotin(IV) dimethoxide and CO 2 can be formed in high yield of up to 92 %, experimentally corroborating the predictions of density functional theory (DFT) calculations. MPC was then separated from the tin oxide residues and converted into phenyl isocyanate. Furthermore, organotin(IV) alkoxides could be regenerated from the tin oxide residues and reused, paving the way for a continuous industrial process. Extension of the scope to the synthesis of diurethanes from toluene 2,4‐diamine and 4,4′‐methylenedianiline could potentially allow the efficient production of industrially relevant diisocyanates.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTElectronic spectroscopy of iron and ruthenium pentamethylcyclopentadienyl-trimethylphosphine complexesRobert G. Bray, John E. Bercaw, Harry B. Gray, Michael D. Hopkins, and Rocco A. PacielloCite this: Organometallics 1987, 6, 5, 922–925Publication Date (Print):May 1, 1987Publication History Published online1 May 2002Published inissue 1 May 1987https://pubs.acs.org/doi/10.1021/om00148a004https://doi.org/10.1021/om00148a004research-articleACS PublicationsRequest reuse permissionsArticle Views166Altmetric-Citations16LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis and reactivity of halide, hydride, and alkyl derivatives of (pentamethylcyclopentadienyl)(bisphosphine)iron(II)Rocco A. Paciello, Juan M. Manriquez, and John E. BercawCite this: Organometallics 1990, 9, 1, 260–265Publication Date (Print):January 1, 1990Publication History Published online1 May 2002Published inissue 1 January 1990https://pubs.acs.org/doi/10.1021/om00115a038https://doi.org/10.1021/om00115a038research-articleACS PublicationsRequest reuse permissionsArticle Views446Altmetric-Citations33LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Abstract The Pd‐catalysed synthesis of sodium acrylate from ethylene and CO 2 in the presence of alcoholate bases has been improved significantly. We used amide solvents such as N ‐cyclohexylpyrrolidone or N , N ‐dibutylformamide to achieve turnover numbers greater than 500 in one run, which is significantly higher than that of systems for this reaction reported previously. For the first time, we were able to recycle the catalyst without any additional regeneration step. With this system, it is possible to use the simple and easily recycled alcoholate base sodium iso propoxide to achieve good turnover numbers up to 200.
The catalytic isomerization of alkenes is a well-studied and valuable process in synthesis. Despite the development of numerous metal-catalyzed isomerization catalysts, methods for the selective isomerization of methylenic enal substrates have not been established. To develop a process for the synthesis of an enal acetate, the so called C5-Acetate that is important in the industrial preparation of vitamin A, we show here that Co(II)-based hydrogen atom transfer catalysts under H2 promote such isomerizations in high yield (often 90%) with low catalyst loading (0.1 mol%). D-labelling studies suggest both the enal isomerization process and catalyst activation by H2 to be reversible.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChain transfer during the aqueous ring-opening metathesis polymerization of 7-oxanorbornene derivativesMarcia B. France, Robert H. Grubbs, Dominic V. McGrath, and Rocco A. PacielloCite this: Macromolecules 1993, 26, 18, 4742–4747Publication Date (Print):August 1, 1993Publication History Published online1 May 2002Published inissue 1 August 1993https://pubs.acs.org/doi/10.1021/ma00070a002https://doi.org/10.1021/ma00070a002research-articleACS PublicationsRequest reuse permissionsArticle Views611Altmetric-Citations49LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
