Aryl halides as convenient precursors of electrogenerated bases. Efficient syntheses of β-oxo nitriles or esters by coupling active-hydrogen groups with esters
RuH 2 (PPh 3 ) 4 -catalyzed reaction of nitriles with terminal alkynes proceeds highly efficiently under neutral conditions to give the corresponding Michael adducts. Furthermore, 1,3-dicarbonyl compounds react with terminal alkynes at the α-position to afford the exo-methylene compounds with high regioselectivity under neutral conditions. The regioselectivity depends upon the change of substrates
RuH 2 (PPh 3 ) 4 催化的腈与末端炔烃的反应在中性条件下高效进行,得到相应的迈克尔加合物。此外,1,3-二羰基化合物在α-位与末端炔烃反应,在中性条件下提供具有高区域选择性的外亚甲基化合物。区域选择性取决于底物的变化。提出了精确的机制。
Process for the production of 3-oxonitriles
申请人:Degussa Aktiengesellschaft
公开号:US04716237A1
公开(公告)日:1987-12-29
3-oxonitriles are produced by reaction of carboxylic acid esters with carboxylic acid nitriles in the presence of 70 to 80% suspension of sodium hydride in white oil. The oxonitrile are intermediate products for the production of 3-oxocarboxylic acid amides or esters and pesticides.
The first enantioselective dearomative [3+2] annulation of 5-amino-isoxazoles with quinonemonoimines was realized using a chiralphosphoricacid as catalyst. Various novel (bridged) isoxazoline fused dihydrobenzofurans bearing two continuous quaternary stereocenters were achieved in moderate to good yields (up to 94%) with moderate to good enantioselectivities (up to 98% ee). The absolute configurations
Dearomative [3+2] annulation of 5-amino-isoxazoles with quinoneimineketals (QIKs) and quinonemonoacetals (QMAs) provided various indoline- or 2,3-dihydrobenzofuran-fused isoxazolines in moderate to good yields with excellent diastereoselectivities.
Reactivity of 7-(2-dimethylaminovinyl)pyrazolo[1,5-<i>a</i>]pyrimidines: Synthesis of pyrazolo[1,5-<i>a</i>]pyrido[3,4-<i>e</i>]pyrimidine derivatives as potential benzodiazepine receptor ligands.<b>1</b>
of 7-methylpyrazolo[1,5-a]pyrimidines were reacted with dimethylformamide dimethylacetal to give the corresponding dimethylaminovinyl derivatives. These were reacted with ammonium acetate affording, through a ring closure, a number of 6-methylpyrazolo[1,5-a]pyrido[3,4-e]pyrimidines bearing various substituents on the pyrazole ring. The 6-acetyl-2-hydroxy-7-methylpyrazolo[1,5-a]pyrimidine was used as
使一系列的7-甲基吡唑并[1,5- a ]嘧啶与二甲基甲酰胺二甲基乙缩醛反应,得到相应的二甲基氨基乙烯基衍生物。它们与乙酸铵反应,通过闭环反应,得到许多在吡唑环上带有各种取代基的6-甲基吡唑并[ 1,5- a ]吡啶基[3,4- e ]嘧啶。将6-乙酰基-2-羟基-7-甲基吡唑并[1,5- a ]嘧啶用作起始原料,以获得一些O-烷基衍生物。2-苄氧基-6-甲基吡唑并[ 1,5- a ]吡啶基[3,4- e ]嘧啶的催化转移氢化反应生成了2-羟基衍生物。