The BF3-catalyzed decomposition of m- and p-substituted α-diazoacetophenones in excess of methyl thiocyanate and ethyl thiocyanate gave the corresponding 2-methylthio-, and 2-ethylthio-5-aryloxazoles, respectively in good yields along with s-alkyl-n-aroylmethylthiocarbamates and α-ethoxyacetophenones. However, yields of 2-dimethylamino-5-aryloxazoles by the reaction of dimethylcyanamide with α-diazoacetophenones
The Acid Catalyzed Decomposition of Diazo Compounds. I. Synthesis of Oxazoles in the BF<sub>3</sub>Catalyzed Reaction of Diazo Carbonyl Compounds with Nitriles
作者:Toshikazu Ibata、Ryohei Sato
DOI:10.1246/bcsj.52.3597
日期:1979.12
The BF3-catalyzed decomposition of diazo carbonyl compounds in nitriles have afforded the corresponding oxazoles in high yields. This method is applicable to diazo carbonyl compounds such as m- and p-substituted diazoacetophenones, ethyl diazoacetate, 1,2-diphenyl-2-diazoethanone, dibenzoyldiazomethane, and dimethyl diazomalonate. Bis(diazo ketone)s such as terminal bis(diazoacetylated) alkanes (III1−4:
[EN] O-ARYL, O-ALKYL, O-ALKENYL AND O-ALKYNYL-MACROLIDES HAVING IMMUNOSUPPRESSIVE ACTIVITY<br/>[FR] MACROLIDES O-ARYLE, O-ALKYLE, O-ALCENYLE ET O-ALCYNYLES IMMUNOSUPPRESSEURS
申请人:MERCK & CO., INC.
公开号:WO1995009857A1
公开(公告)日:1995-04-13
(EN) Substituted compounds of the FK-506 Type. These compounds are useful for the same or essentially the same purposes as FK-506 and are applied in the same or a similar manner. These compounds are immunosuppressants and useful for the treatment of autoimmune diseases, infectious diseases and/or the prevention of rejection of foreign organ transplants. Still other uses are described in the disclosure.(FR) On décrit des composés qui peuvent se substituer au type FK-506 et servent aux mêmes fins ou presque que FK-506 et s'utilisent de façon identique ou similaire. Ces composés sont immunosuppresseurs et permettent de traiter des maladies auto-immunes ou infectieuses et/ou de prévenir le rejet de greffes d'organes étrangers. La description présente aussi d'autres exemples d'utilisation.
Selective alkylation of indazoles is still a highly challenging topic in chemistry and the synthesis of important molecules. Herein, a novel highly selective N2-alkylation of indazoles with diazo compounds is described in the presence of TfOH. Unlike the traditional metal- and base-catalysed version, this protocol highlights the regioselectivity of alkylation of indazoles and a metal-free catalysis
吲唑的选择性烷基化仍然是化学和重要分子合成中极具挑战性的课题。在此,描述了在 TfOH 存在下,吲唑与重氮化合物的新型高选择性N 2 -烷基化。与传统的金属和碱催化版本不同,该方案突出了吲唑烷基化的区域选择性和无金属催化体系,以高区域选择性( N 2 / N 1高达 100/0) 和出色的官能团耐受性。此外,成功地进行了克级合成以产生相应的产物。通过控制实验进行的机械研究提供了合理的机械建议。
TfOH-Catalyzed Regioselective S–H Insertion of Cyclic Thioamide Derivatives with Diazo Compounds at Room Temperature
We have developed a method for highly regioselective S–H bond insertion reactions of various diazo compounds and cyclic thioamide derivatives at room temperature. These reactions provide straightforwardaccess to alkylated benzimidazoles, benzothiazoles, and benzoxazoles. This mild method uses readily available TfOH as a catalyst and features a broad substrate scope, good functional group tolerance