Cycloadditions of 3-Amino-2H-1,4-oxazin-2-ones with Olefins: Generation of 5,6-Dihydro-2-oxo-2H-pyran-6-carbonitriles.
摘要:
The Diels-Alder adducts from the reaction of 3-amino-2H-1,4-oxazin-2-ones 1b-d with olefins in toluene at reflux, undergo ring transformations yielding previously unknown 5,6-dihydro-2-oxo-2H-pyran-6-carbonitriles 3. In some cases the latter are converted into 5-amino-2,4-pentadienenitriles 4. A plausible mechanism is proposed.
通过与取代的炔属化合物的环加成消除反应,合成3-官能化的5-氯-6-甲基-2 H -1,4-恶嗪-2-酮和吡啶。
摘要:
通常在适当的条件下,通过亲电催化避免内酯功能的反应,在3,5-二氯-6-甲基-2 H -1,4-恶嗪-2-酮中实现氯亚胺基的选择性官能化。已表明3-取代的5-氯-6-甲基-2 H -1,4-恶嗪-2-酮中的氮杂二烯体系易于与单取代的炔属化合物反应,并通过环加成消除法以优异的收率得到多官能化吡啶。讨论了通常较高的区域选择性及其对3-取代基性质的依赖性。
The Synthesis of 3-Functionalized 5-chloro-6-methyl-2H-1,4-oxazin-2-ones and of pyridines from cycloaddition-elimination reactions with substituted acetylenic compounds.
作者:Koen J. Van Aken、Gerrit M. Lux、Geert G. Deroover、Lieven Meerpoel、Georges J. Hoornaert
DOI:10.1016/s0040-4020(01)90431-4
日期:1994.4
electrophilic catalysis avoiding reaction of the lactone function. The azadiene system in the 3-substituted 5-chloro-6-methyl-2H-1,4-oxazin-2-ones is shown to react easily with monosubstituted acetyleniccompounds yielding polyfunctionalized pyridines in excellent yield via a cycloaddition-elimination process. The usually high regioselectivity and its dependence on the nature of the 3-substituent is discussed
通常在适当的条件下,通过亲电催化避免内酯功能的反应,在3,5-二氯-6-甲基-2 H -1,4-恶嗪-2-酮中实现氯亚胺基的选择性官能化。已表明3-取代的5-氯-6-甲基-2 H -1,4-恶嗪-2-酮中的氮杂二烯体系易于与单取代的炔属化合物反应,并通过环加成消除法以优异的收率得到多官能化吡啶。讨论了通常较高的区域选择性及其对3-取代基性质的依赖性。
Cycloadditions of 3-Amino-2H-1,4-oxazin-2-ones with Olefins: Generation of 5,6-Dihydro-2-oxo-2H-pyran-6-carbonitriles.
作者:Christine C. Fannes、Georges J. Hoornaert
DOI:10.1016/0040-4039(92)88138-u
日期:1992.4
The Diels-Alder adducts from the reaction of 3-amino-2H-1,4-oxazin-2-ones 1b-d with olefins in toluene at reflux, undergo ring transformations yielding previously unknown 5,6-dihydro-2-oxo-2H-pyran-6-carbonitriles 3. In some cases the latter are converted into 5-amino-2,4-pentadienenitriles 4. A plausible mechanism is proposed.