An efficient non-reductive synthesis of 3-aminomethylindole (6) was developed from gramine (1) via 3-phthalimidomethylindole (2). The reactions of amine 6 with substituted methyl dithiobenzoates gave 3-(arylthiocarbonylaminomethyl)indoles. The Hugerschoff ring-closure reactions of the thiobenzamide intermediates (11a–f) with phenyltrimethylammonium tribromide and subsequent basic treatment furnished
一种有效的非还原性合成的3-氨基甲基吲哚(6)是由草胺(1)通过3-phthalimidomethylmethylindole(2)合成的。胺6与取代的二硫代苯甲酸甲酯的反应得到3-(芳基硫代羰基氨基甲基)吲哚。硫代苯甲酰胺中间体(11a – f)与苯基三甲基三溴化铵的Hugerschoff闭环反应和随后的基本处理提供了2-芳基噻嗪[6,5- b ]吲哚衍生物(14a – f)。通过使用后者的溴源,植物抗毒素环油菜籽素(8制备)的产率要比先前所述的高得多。通过IR,1 H和13 C NMR光谱,包括2D-HMQC,2D-HMBC和DEPT测量,阐明了新产品的结构。
Sequential One-Pot Synthesis of Tri- and Tetrasubstituted Thiophenes and Fluorescent Push–Pull Thiophene Acrylates Involving (Het)aryl Dithioesters as Thiocarbonyl Precursors
作者:Anand Acharya、G. Parameshwarappa、B. Saraiah、H. Ila
DOI:10.1021/jo502429c
日期:2015.1.2
An efficient, one-pot three component synthesis of highly functionalized tri- and tetrasubstituted thiophenes has been reported involving (het)aryl dithioesters as thiocarbonyl precursors. Thus, sequential base mediated condensation of readily available (het)aryl active methylene ketones with (het)aryl dithioesters followed by S-alkylation of the resulting enethiolate salts with activated halomethylene
dithiobenzoates. The Hugerschoff reactions of thiobenzamides (14a–e) with phenyltrimethylammonium tribromide provided the rare title 2-arylthiazino[5,6-b]indoles (15a–e) in good yields. A convenient one-pot approach for the synthesis of 2-phenyl-1,3-thiazino[5,6-b]indole (15a) from 2-aminomethylindole (9) is also described.
通过使2-氨基甲基吲哚(9)与取代的苯甲酰氯反应,然后使用Lawesson试剂进行硫化,可以制备2-硫代苯甲酰胺基甲基吲哚衍生物(14a – e)。或者,这些硫代酰胺是在胺存在下,或在室温下借助取代的二硫代苯甲酸甲酯,通过使用取代的苯甲醛以一种有效的方式,从胺中一步一步地从胺中获得的。硫代苯甲酰胺(14a – e)与三溴化苯基三甲基铵的Hugerschoff反应提供了罕见的标题2-芳基噻嗪[5,6- b ]吲哚(15a – e),收益率很高。还描述了一种方便的一锅法,由2-氨基甲基吲哚(9)合成2-苯基-1,3-噻嗪并[5,6- b ]吲哚(15a)。
An Easy Access to 4,5-Disubstituted Thiazoles via Base-Induced Click Reaction of Active Methylene Isocyanides with Methyl Dithiocarboxylates
5-diarylthiazoles. An efficient synthesis of 4,5-disubstituted thiazoles via base-induced cyclization of active methylene isocyanides such as tosylmethyl isocyanide, ethyl isocyanoacetate, and arylmethyl isocyanides with methyl arene- and hetarenecarbodithioates is reported. This synthesis could be a new click chemistry reaction, since it is simple, rapid, and often avoids purification steps. In addition
Ligand- and catalyst-free intramolecular C-S bond formation: direct access to indalothiochromen- 4-ones
作者:T.A. Jenifer Vijay、Nagarakere C. Sandhya、C.S. Pavankumar、Kanchugarakoppal S. Rangappa、Kempegowda Mantelingu
DOI:10.1515/hc-2014-0206
日期:2015.6.1
Abstract
An efficient ligand- and catalyst-free intramolecular S-arylation leading to the direct synthesis of indalothiochromen-4-ones from simple dithioesters under mild conditions has been developed. This method is particularly noteworthy given its experimental simplicity, high generality, and good functional group toleration.