2362-79-0Relevant articles and documents
Experimental and theoretical investigation of benzyl-N-pyrrolylketene, one- step procedure for preparing of new β-lactams by [2 +2] cycloaddition reaction
Behzadi, Masoumeh,Saidi, Kazem,Islami, Mohammad Reza,Khabazzadeh, Hojatollah
, p. 111 - 117 (2016)
3-Phenyl-2-(1-H-pyrrol-1-yl) propanoic acid has been used as a ketene source in synthesizing of monocyclic-2-azetidinones. Hindrance in ketene and imines successfully controlled the diastereoselectivity of the reaction. For example, in some cases only one isomer was achieved. By using Mukaiyama reagent, the leaving group in acid was activated and the by-products were separated by simple aqueous work-up. DFT calculation indicated that the benzyl-N-pyrrolylketene has nonconjugated structure and the pyrrolyl ring is perpendicular to the ketene plane in both the twisted and planar structures.
Cobalt-Catalyzed Deoxygenative Hydroboration of Nitro Compounds and Applications to One-Pot Synthesis of Aldimines and Amides
Gudun, Kristina A.,Zakarina, Raikhan,Segizbayev, Medet,Hayrapetyan, Davit,Slamova, Ainur,Khalimon, Andrey Y.
, p. 601 - 611 (2021/11/30)
The commercially available and bench-stable Co(acac)2 ligated with bis[(2-diphenylphosphino)phenyl] ether (dpephos) was employed for selective room temperature hydroboration of nitro compounds with HBPin (TOF up to 4615 h?1), tolerating halide, hydroxy, amino, ether, ester, lactone, amide and heteroaromatic functionalities. These reactions offered a direct access to a variety of N-borylamines RN(H)BPin, which were in situ treated with aldehydes and carboxylic acids to produce a series of aldimines and secondary carboxamides without the need for dehydrating and/or coupling reagents. Combination of these transformations in a sequential one-pot manner allowed for direct and selective synthesis of aldimines and secondary carboxamides from readily available and inexpensive nitro compounds.
Visible-Light-Induced Cycloaddition of α-Ketoacylsilanes with Imines: Facile Access to β-Lactams
Ye, Jian-Heng,Bellotti, Peter,Paulisch, Tiffany O.,Daniliuc, Constantin G.,Glorius, Frank
supporting information, p. 13671 - 13676 (2021/05/11)
We report the synthesis of β-lactams from α-ketoacylsilanes and imines, which proceeds via a formal [2+2] photochemical cycloaddition with in situ generation of siloxyketene. This mild and operationally simple reaction proceeds in an atom-economic fashion with broad substrate scope, including aldimines, ketimines, hydrazones, and fused nitrogen heterocycles, affording a variety of important β-lactams with satisfactory diastereoselectivities in most cases. This reaction also features good functional-group tolerance, facile scalability and product diversification. Experimental and computational studies suggest that α-ketoacylsilanes can serve as photochemical precursors by engaging in a 1,3 silicon shift to the distal carbonyl group.