Organic Synthesis International: December 2016

Monday, 26 December 2016

Eco-Friendly, Catalyst and Solvent-Free, Synthesis of Acetanilides and N-Benzothiazole-2-yl-acetamides

N-(o-Tolyl)acetamide (3b) White solid, 51.5 mg, 71% yield; m.p. 108.4-109.0 °C (Lit.27 108-109 °C); IR (KBr) n / cm-1 3291, 1647, 1587, 1527, 1458, 1369, 1271, 1116, 1039, 933, 854, 756, 698, 651, 607; 1H NMR (500 MHz, CDCl3) d 2.19 (s, 3H, CH3), 2.30 (s, 3H, CH3), 7.10 (t, 1H, J 7.5 Hz, CH), 7.21 (t, 1H, J 8.0 Hz, CH), 7.71 (d, 1H, J 8.0 Hz, CH); 13C NMR (125 MHz, CDCl3) d 17.8, 24.2, 123.7, 125.4, 126.7, 129.7, 130.5, 135.6, 168.6.

Short ReportJ. Braz. Chem. Soc. 2016

Eco-Friendly, Catalyst and Solvent-Free, Synthesis of Acetanilides and N-Benzothiazole-2-yl-acetamides

Silvio Cunha; Lourenço L. B. de Santana

An expeditious and green synthesis of acetamides is described in good yield without external heating, and with simple purification.

This paper is part of the PubliSBQ Special Issue in honor of the late Prof Angelo da Cunha Pinto.

http://dx.doi.org/10.21577/0103-5053.20160265

Published online: September 27, 2016.

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Synthesis of symmetrical pyridines by iron-catalyzed cyclization of ketoxime acetates and aldehydes

Synthesis of symmetrical pyridines by iron-catalyzed cyclization of ketoxime acetates and aldehydes

Green Chem., 2017, Advance Article
DOI: 10.1039/C6GC03137D, Paper

YuKun Yi, Mi-Na Zhao, Zhi-Hui Ren, Yao-Yu Wang, Zheng-Hui Guan
A facile iron-catalyzed cyclization of aldehydes with ketoxime acetates for the synthesis of multisubstituted symmetrical pyridines has been developed.

Synthesis of symmetrical pyridines by iron-catalyzed cyclization of ketoxime acetates and aldehydes

YuKun Yi,^a Mi-Na Zhao,^a Zhi-Hui Ren,^a Yao-Yu Wang^a and Zheng-Hui Guan*^a

Corresponding authors

Key Laboratory of Synthetic and Nature Molecule Chemistry of Ministry of Education, Department of Chemistry & Materials Science, Northwest University, Xi'an 710127, P.R. China
E-mail: guanzhh@nwu.edu.cn

Green Chem., 2017, Advance Article

DOI: 10.1039/C6GC03137D

http://pubs.rsc.org/en/Content/ArticleLanding/2017/GC/C6GC03137D?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

A novel and facile iron-catalyzed cyclization of ketoxime acetates and aldehydes for the green synthesis of substituted pyridines has been developed. In the presence of a FeCl₃ catalyst, this reaction exhibited a good functional group tolerance to produce 2,4,6-triarylsubstituted symmetrical pyridines in high yields in the absence of any additive. A gram-scale reaction sequence was performed to demonstrate the scaled-up applicability of this synthetic method.

4-Phenyl-2,6-di-p-tolylpyridine (3bb). Yield 70% (47.0 mg); Yellow solid; mp 148-150 o C; S-3

1 H NMR (400 MHz, CDCl3): δ 8.09 (d, J = 8.0 Hz, 4H), 7.82 (s, 2H), 7.72 (d, J = 7.2 Hz, 2H), 7.52-7.45 (m, 3H), 7.31 (d, J = 8.0 Hz, 4H), 2.42 (s, 6H).

13C NMR (100 MHz, CDCl3): δ 157.3, 149.9, 139.2, 138.9, 136.8, 129.4, 129.0, 128.8, 127.1, 126.9, 116.5, 21.3.

HRMS Calcd (ESI) m/z for C25H22N: [M+H] + 336.1747. Found: 336.1731.

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