Convenient Synthesis of 4-Methylene-2-oxazolidinones and 4-Methylenetetrahydro-1,3-oxazin-2-ones via Transition-Metal Catalyzed Intramolecular Addition of Nitrogen Atom to Acetylenic Triple Bond
作者:Yoshinao Tamaru、Masanari Kimura、Shuji Tanaka、Sigeru Kure、Zen-ichi Yoshida
DOI:10.1246/bcsj.67.2838
日期:1994.10
2-Propynyl tosylcarbamates 1 undergo cyclization smoothly by the catalysis of CuCl/Et3N or AgNCO/Et3N to furnish 4-methylene-2-oxazolidinones 2 in good yields. The similar cyclization of the N-acyl derivatives of 1 (PhCO, MeCO, EtOCO, etc.) is catalyzed effectively by AgNCO/t-BuOK. These reactions accommodate a variety of substituents at C1 and C3 of 2-propyn-1-ol and provide (Z)-2 as single stereoisomers. The scope of the cyclization of 3-butynyl carbamates is rather limited, and in general only N-tosyl derivatives of terminally unsubstituted 3-butyn-1-ols undergo cyclization to give 4-methylenetetrahydro-1,3-oxazin-2-ones in synthetically useful yields by the catalysis of AgNCO/Et3N or AgNCO/t-BuOK.
Palladium-Catalyzed Intramolecular Hydroamination of Propargylic Carbamates and Carbamothioates
作者:Santosh Kumar Alamsetti、Andreas K. Å. Persson、Jan-E. Bäckvall
DOI:10.1021/ol5002279
日期:2014.3.7
An efficient and simple methodology was developed for the synthesis of oxazolidinones, oxazolidinthiones, imidazolidinthiones, and imidazolidinones from the corresponding propargylic starting materials using Pd(OAc)2 and n-Bu4NOAc as catalysts in DCE at room temperature.
开发了一种有效且简单的方法,用于在室温下在DCE中使用Pd(OAc)2和n- Bu 4 NOAc作为催化剂,从相应的炔丙基原料合成恶唑烷酮,恶唑烷硫酮,咪唑烷硫酮和咪唑烷酮。
5-Exo-dig aminocylization/hydroxyfluorination of propargylic carbamates
作者:Antonio Arcadi、Marco Chiarini、Luana Del Vecchio、Fabio Marinelli
DOI:10.1016/j.jfluchem.2018.04.002
日期:2018.7
The reaction was effectively promoted by NaHCO3 and/or silver catalysis. The peculiar behavior of propargylic carbamates bearing a chiral steroidal moiety is described. Extensions and limitations of the procedure with respect to urea derivatives, homopropargyl compounds, internal alkynes and one-pottransformations of propargylic alcohols with isocyanates are reported.
Scalable Synthesis of Oxazolones from Propargylic Alcohols through Multistep Palladium(II) Catalysis: β-Selective Oxidative Heck Coupling of Cyclic Sulfonyl Enamides and Aryl Boroxines
作者:Santosh Kumar Alamsetti、Andreas K. Å. Persson、Tuo Jiang、Jan-E. Bäckvall
DOI:10.1002/anie.201307471
日期:2013.12.16
unusual β selectivity to generate a variety of branched substituted oxazolones (see scheme; Ts=p‐toluenesulfonyl). The three‐step synthesis from readilyavailable starting materials with a simple palladium catalyst and inexpensive reagents could be carried out in a single reaction vessel or scaled up for the preparation of large amounts of these amino acid precursors.
Palladium(II)-Catalyzed Enantio- and Diastereoselective Synthesis of Pyrrolidine Derivatives
作者:Ranjan Jana、Tejas P. Pathak、Katrina H. Jensen、Matthew S. Sigman
DOI:10.1021/ol3016989
日期:2012.8.17
A palladium-catalyzed enantio- and diastereoselective synthesis of pyrrolidine derivatives is described. Initial intramolecular nucleopalladation of the tethered protected amine forms the pyrrolidine moiety and a quinone methide intermediate. A second nucleophile adds intermolecularly to afford diverse products in high enantio- and diastereoselectivity.