3,1-Benzoxazine und Tetrahydrochinazoline auso-Aminobenzylalkohol undo-Aminobenzylamin - Semi-empirische MO-Berechnungen zum Cyclisierungsverhalten
作者:Jürgen Lessel
DOI:10.1002/ardp.19943270510
日期:——
kondensiert mit Aldehyden und Ketonen zu den 3,1‐Benzoxazinen 20a/b und 22a/b, mit β‐Diketonen hingegen entstehen die Enaminderivate 24a‐c. Mit dem isosteren o‐Aminobenzylamin (1) ergeben sich als heterocyclische Produkte die Tetrahydrochinazoline 11a/b und 14b, 1,4‐Diamine wie 2 und 3 reagieren zu den offenkettigen Verbindungen 15, 16b, 18a und 19. Das unterschiedliche Verhalten kann mit den Reaktionsenthalpien
Cu/N-ligand/TEMPO catalytic system was first applied to the aerobic oxidative synthesis of heterocycles. As demonstrated, 2-substituted quinazolines and 4H-3,1-benzoxazines were synthesized efficiently from the one-pot reaction of aldehydes with 2-aminobenzylamines and 2-aminobenzyl alcohols, respectively, by employing CuCl/DABCO/4-HO-TEMPO as the catalysts and oxygen as the terminal oxidant.
Cu / N-配体/ TEMPO催化体系首先被用于杂环的好氧氧化合成。如所证明的,通过使用CuCl / DABCO / 4-HO-TEMPO分别由醛与2-氨基苄胺和2-氨基苄醇的一锅反应有效地合成了2-取代的喹唑啉和4 H -3,1-苯并恶嗪。作为催化剂,氧气作为末端氧化剂。
Highly Efficient One-Pot Synthesis of 2-Substituted Quinazolines and 4<i>H</i>-Benzo[<i>d</i>][1,3]oxazines<i>via</i>Cross Dehydrogenative Coupling using Sodium Hypochlorite
describes a catalyst-free synthesis of 2-substitutedquinazolines and 4H-benzo[d][1,3]oxazines using commericially available sodiumhypochlorite as oxidant. Operational simplicity, mild reaction conditions and the ability to construct structurally diverse 2-quinazolines and 2-substituted4H-benzo[d][1,3]oxazines by this method render it to be a practical alternative for the synthesis of these heterocycles
该通报描述了使用市售的次氯酸钠作为氧化剂的无催化剂合成2-取代的喹唑啉和4 H-苯并[ d ] [1,3]恶嗪。操作简便,反应条件温和以及通过该方法构造结构上不同的2-喹唑啉和2-取代的4 H-苯并[ d ] [1,3]恶嗪的能力使其成为合成这些杂环的实用选择。
Simple grinding-induced reactions of 2-aminobenzyl alcohol and benzaldehyde derivatives, a rapid synthetic route to 3,1-benzoxazines
作者:I. B. Masesane、E. Muriithi、T. H. Tabane
DOI:10.4314/bcse.v28i2.14
日期:——
The grinding-induced reactions of 2-aminobenzyl alcohol and benzaldehyde derivatives in the presence of 30 mol% of acetic acid to give 3,1-benzoxazines are described. The reactions were performed at room temperature affording 3,1-benzoxazines in yields above 95% and high purity when benzaldehyde and its chloro and nitro derivatives were used. KEY WORDS : 2-Aminobenzyl alcohol, Benzaldehyde, Acetic acid