Straightforward synthesis of 4,5-bifunctionalized 1,2-oxazinanes via Lewis acid promoted regio- and stereo-selective nucleophilic ring-opening of 3,6-dihydro-1,2-oxazine oxides
The Application of 1,2-Oxazinanes as Chiral Cyclic Weinreb Amide-Type Auxiliaries Leading to a Three-Component, One-Pot Reaction
作者:Gerhard Hilt、Jan Fährmann、Ludmila Hermann
DOI:10.1055/a-1683-0484
日期:2022.4
1,2-Oxazines were synthesised via a copper-catalysed aerobic acylnitrosoDiels–Alderreaction from 1,4-disubstituted 1,3-dienes and N-Boc-hydroxylamine. From this, 1,2-oxazinanes were obtained in a novel follow-up reaction path. The stability of several 1,2-oxazines and 1,2-oxazinanes towards organometallic compounds was tested to rate their operability as cyclic chiral Weinreb amide auxiliaries.
Formation and dienophilic reactions of transient C-nitrosocarbonyl compounds
作者:Gordon W. Kirby、James G. Sweeny
DOI:10.1039/p19810003250
日期:——
= Ac)followed by rapid capture of nitrosocarbonylmethane by thebaine. The related adduct (6; R = PhCO) behaved similarly. DMA adducts of the type (6) are valuable in studies on the reactions of nitrosocarbonyl compounds, especially with co-reactants sensitive to oxidation. Thus (6; R = Ac) and 1,3-diphenylisobenzofuran (7) reacted cleanly in benzene at 80°C to give the O-acetyloxime (10) of 1,2-dibenzoylbenzene
在共轭二烯蒂巴因(1)存在下,用高碘酸四乙铵氧化苯并异羟肟酸,可高收率得到环加合物6β,14β-(N-苯甲酰环氧亚氨基)-6,14-二氢蒂巴因(2; R = Ph)。类似地使用乙酰氧肟酸制备相应的N-乙酰基衍生物(2; R = Me)。同样地,从丁-1,3-二烯获得2-苯甲酰基-和2-乙酰基-3,6-二氢-2 H -1,2-恶嗪(5; R = Ph)和(5; R = Me) ,以及N-苯甲酰基和N来自9,10-二甲基蒽(DMA)的9,10-环氧亚氨基-9,10-二氢-9,10-二甲基蒽的-乙酰基衍生物(6; R = PhCO)和(6; R = Ac)。据信这些反应涉及亚硝基羰基苯或亚硝基羰基甲烷的形成,它们是一类新的瞬时反应性物质的代表。在蒂巴因(1)存在的情况下,在60°C下苯中的环加合物(6; R = Ac)分解,得到蒂巴因加合物(2; R = Me)和DMA。观察到DMA释放的一级动力学,这与加合物(6;
Wichterle; Novak, Collection of Czechoslovak Chemical Communications, 1950, vol. 15, p. 309,313
作者:Wichterle、Novak
DOI:——
日期:——
Synthesis of unsaturated [1,2]oxazines by using sigmatropic rearrangements and the ring-closing metathesis reaction
作者:Alexandre Le Flohic、Christophe Meyer、Janine Cossy、Jean-Roger Desmurs
DOI:10.1016/j.tetlet.2003.09.125
日期:2003.11
Various substituted unsaturated [1,2]oxazines have been synthesized by using a [2,3]- or a [3,3]-sigmatropic rearrangement and a ring-closing metathesis reaction as key steps. (C) 2003 Published by Elsevier Ltd.