Novel Five/Five- and Six/Five-Membered Bicyclic Nitroso Acetals from High-Pressure-Promoted Cyclisation Reactions ofp-Methoxybenzyl Vinyl Ether, 1-Nitro-2-heteroaryl Ethenes, and Mono- and Di-Substituted Olefins
作者:George J. T. Kuster、Ruud H. J. Steeghs、Hans W. Scheeren
DOI:10.1002/1099-0690(200102)2001:3<553::aid-ejoc553>3.0.co;2-n
日期:2001.2
three-component cycloaddition with p-methoxybenzyl vinyl ether (1) and methyl acrylate to yield novel heteroaromatic-substituted six/five-membered bicyclic nitroso acetals. In the reaction of 3-[(E)-2-nitroeth-1-enyl]pyridine (2 equiv.) and 1 a competition between the formation of the tandem [4 + 2]/[3 + 2] cycloadducts and the formation of a novel five-membered cyclic nitronate was observed. The ratio
在 15 kbar 下,1-硝基-2-杂芳基乙烯 2a-c 在一锅三组分环加成反应中与对甲氧基苄基乙烯基醚 (1) 和丙烯酸甲酯反应,生成新型杂芳烃取代的六元/五元双环亚硝基缩醛. 在 3-[(E)-2-nitroeth-1-enyl] 吡啶 (2 当量) 和 1 a 的反应中,串联 [4 + 2]/[3 + 2] 环加合物的形成与形成之间的竞争观察到了一种新型五元环状硝基酸酯。产物形成的比率强烈地依赖于压力和溶剂。已经提出了形成新型五元环状硝基的机理解释。1-Nitro-4-[(E)-2-nitroeth-1-enyl] 苯 (2d) 与 1 以与 2a 相同的方式根据建议的机制反应。五元环状硝基酸酯反应为 1,