785-80-8Relevant articles and documents
A DFT and experimental study of the spectroscopic and hydrolytic degradation behaviour of some benzylideneanilines
Nelson, Peter N.,Robertson, Tahjna I.
, (2021/10/12)
The spectroscopic and hydrolytic degradation behaviour of some N-benzylideneanilines are investigated experimentally and theoretically via high quality density function theoretical (DFT) modelling techniques. Their absorption and vibrational spectra, accurately predicted by DFT calculations, are highly dependent on the nature of the substituents on the aromatic rings, hence, though some of their spectroscopic features are similar, energetic differences exist due to differences in their electronic structures. Whereas the o-hydroxy aniline derived adducts undergo hydrolysis via two pathways, the most energetically economical of which is initiated by a fast enthalpy driven hydration, over a conservative free energy (ΔG?) barrier of 53 kJ mol?1, prior to the rate limiting entropy controlled lysis step which occurs via a conservative barrier of ca.132 kJ mol?1, all other compounds hydrolyse via a slower two-step pathway, limited by the hydration step. Barriers heights for both pathways are controlled primarily by the structure and hence, stability of the transition states, all of which are cyclic for both pathways.
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.
Ionic-Liquid-Catalyzed Synthesis of Imines, Benzimidazoles, Benzothiazoles, Quinoxalines and Quinolines through C?N, C?S, and C?C Bond Formation
Adimurthy, Subbarayappa,Badhani, Gaurav,Joshi, Abhisek
, p. 6705 - 6716 (2021/12/31)
We report the tetramethyl ammonium hydroxide catalyzed oxidative coupling of amines and alcohols for the synthesis of imines under metal-free conditions by utilizing oxygen from air as the terminal oxidant. Under the same conditions, with ortho-phenylene diamines and 2-aminobenzenethiols the corresponding benzimidazoles and benzothiazoles were obtained. Quinoxalines were obtained from ortho-phenylene diamines and 1-phenylethane-1,2-diol, the conditions were then extended to the synthesis of quinoline building blocks by reaction of 2-amino benzyl alcohols either with 1-phenylethan-1-ol or acetophenone derivatives. The formation of C?N, C?S and C?C bonds was achieved under metal-free conditions. A broad range of amines (aromatic, aliphatic, cyclic and heteroaromatic) as well as benzylic alcohols including heteroaryl alcohols reacted smoothly and provided the desired products. The mild reaction conditions, commercially available catalyst, metal-free, good functional-group tolerance, broad range of products (imines, benzimidazoles, benzothiazoles, quinoxalines and quinolines) and applicability at gram scale reactions are the advantages of the present strategy.
