一般合成3-芳基取代的吡唑并[5,1- c ] [1,4]苯并恶嗪和吡唑并[1,5- a ] [1,4]苯并二氮杂-6(4 H)-ones的有效策略† ‡
摘要:
一般合成3-芳基取代的吡唑并[5,1- c ] [1,4]苯并恶嗪和吡唑并[1,5- a ] [1,4]苯并二氮杂-6(4 H)-的有效策略是用分子内的1,3-偶极环加成反应开发了R.N.。通过一锅法进行的两步反应,可以轻松获得环加合物的前体酰肼基氯。然后将其未经纯化用于碱基诱导的亚硝胺的形成,其随后进行原位用炔烃进行分子内环加成反应,得到所需产物。该反应方案也已应用于双异环和生物感兴趣的尿嘧啶衍生物的合成中。该方法的操作简单,使用廉价的起始原料以及所需的相对较短的反应时间使该方法方便实用。
一般合成3-芳基取代的吡唑并[5,1- c ] [1,4]苯并恶嗪和吡唑并[1,5- a ] [1,4]苯并二氮杂-6(4 H)-ones的有效策略† ‡
摘要:
一般合成3-芳基取代的吡唑并[5,1- c ] [1,4]苯并恶嗪和吡唑并[1,5- a ] [1,4]苯并二氮杂-6(4 H)-的有效策略是用分子内的1,3-偶极环加成反应开发了R.N.。通过一锅法进行的两步反应,可以轻松获得环加合物的前体酰肼基氯。然后将其未经纯化用于碱基诱导的亚硝胺的形成,其随后进行原位用炔烃进行分子内环加成反应,得到所需产物。该反应方案也已应用于双异环和生物感兴趣的尿嘧啶衍生物的合成中。该方法的操作简单,使用廉价的起始原料以及所需的相对较短的反应时间使该方法方便实用。
Palladium-Catalyzed Heteroannulation Leading to Heterocyclic Structures with Two Heteroatoms: A Highly Regio- and Stereoselective Synthesis of (<i>Z</i>)-4-Alkyl-2-alkyl(aryl)idene-3,4-dihydro-2<i>H</i>-1,4-benzoxazines and (<i>Z</i>)-3-Alkyl(aryl)idene-4-tosyl-3,4-dihydro-2<i>H</i>-1,4-benzoxazines
作者:Nitya G. Kundu、Gopeswar Chaudhuri、Anup Upadhyay
DOI:10.1021/jo000826j
日期:2001.1.1
triethylamine at room temperature to yield 2-[N-alkyl(benzyl)-N-(3-aryl-prop-2'-ynyl)]-aminophenyl tosylates 8 in extremely good yields (72-96%). The latter could then be cyclized with KOH in ethanol-water to Z-9 in a highlyregio- and stereoselective manner. Similarly, palladium-copper-catalyzed reaction of 2-(prop-2'-ynyloxy)aniline (21) with aryl iodides 7 led to 22-26 which after tosylation and cyclization
Synthesis and Highly Enantioselective Hydrogenation of Exocyclic Enamides: (<i>Z</i>)-3-Arylidene-4-acetyl-3,4-dihydro-2<i>H</i>- 1,4-benzoxazines
作者:Yong-Gui Zhou、Peng-Yu Yang、Xiu-Wen Han
DOI:10.1021/jo048212s
日期:2005.3.1
Highly enantioselective hydrogenation of exocyclic enamides, (Z)-3-arylidene-4-acyl-3,4-dihydro-2H-benzoxazines, was achieved in up to 98.6% ee by using Rh/(R,R)-Me-Duphos complex as the catalytic system. The absolute configuration of the product was assigned as R by chemical interrelations.