A convenient synthesis of 3- and 5-amino-1H-pyrazoles via 3(5)-amino-4-(ethylsulfinyl)-1H-pyrazole desulfinylation
摘要:
Syntheses of 5-amino-3-aryl- and 3-amino-5-aryl-1H-pyrazoles from beta-bromo-alpha-(ethylsulfanyl)cinnamonitrile are described. The beta-bromo-alpha-(ethylsulfanyl) cinnamonitriles were oxidized with H(2)O(2) to the corresponding beta-bromo-alpha-(ethylsulfinyl) cinnamonitriles. Subsequent treatment of the resulting sulfoxides with hydrazine hydrate or methylhydrazine followed by hydrochloric acid hydrolysis afforded 5-amino-3-aryl- and 3-amino-5-aryl-1H-pyrazoles, respectively, in good yields.
Reaction of beta-bromo alpha-alkylthiocinnamonitriles with various substituted methyl salicylates followed by treatment with AlCl3/PhNO2 provides 3-cyanoflavones. (C) 2003 Elsevier Ltd. All rights reserved.
Voie d'accès aux amino-6 cyano-3-1H-pyridones-2 substituées en 5 par un groupement SR
作者:F Pochat
DOI:10.1016/s0040-4039(00)94044-9
日期:1983.1
The reaction with cyanacetamide of bromoderivatives , obtained from aldehydes, gives access to 6-amino-3-cyano-2 (1H) pyridones . A non cyclized intermediate was isolated; 13C NMR data are reported.
由醛获得的溴代衍生物与氰乙酰胺的反应可得到6-氨基-3-氰基-2(1H)吡啶酮。分离出非环化中间体。报告了13 C NMR数据。
Voie d'accès aux amino-5 isoxazoles substitués en 4 par un groupement SR
作者:Francis Pochat
DOI:10.1016/0040-4039(80)80170-5
日期:1980.1
The reaction with hydroxylamine of bromoderivatives 2, obtained from aldehydes, provides, in most cases with good yields, 5-isoxazolamines 3. 13C NMR data are given.
由醛获得的溴代衍生物2与羟胺的反应在大多数情况下以良好的产率提供了5-异恶唑胺3。给出了13 C NMR数据。
New Approach to 3‐Aminothiophene‐ 2‐carboxylic Acid Derivatives: Access to 5‐Aryl‐4‐(ethylsulfanyl) Compounds
Treatment of DMSO/water solutions of β‐bromo‐α‐(ethylsulfanyl)cinnamonitriles with sodium sulphide and α‐halo acetic acidsderivatives followed by cyclization in a potassium carbonate/acetone/DMSO mixture gave the expected 3‐amino‐5‐aryl‐4‐(ethylsulfanyl)thiophene‐2‐carboxylic acidsderivatives in fair yields.