𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Synthesis of novel 5-chlorinated 2-aminothiophenes using 2,5-dimethylpyrrole as an amine protecting group

✍ Scribed by Zita Puterová; Tomáš Bobula; Daniel Végh


Publisher
Journal of Heterocyclic Chemistry
Year
2008
Tongue
English
Weight
510 KB
Volume
45
Category
Article
ISSN
0022-152X

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

magnified image

A new synthetic methodology towards substituted 2‐amino‐5‐chlorothiophenes is described. Compounds of this type are important as building blocks for oligomers used in polymer research. Easily available 2‐aminothiophenes underwent Paal‐Knorr reaction to protect the free amino group before electrophilic substitution. Although the chlorination was predicted to proceed at the thiophene ring, only free positions of 2,5‐dimethylpyrrole were substituted. To direct chlorination to the thiophene ring acetamido derivative was prepared first and then chlorinated. Transamination with hexane‐2,5‐dione created a 2,5‐dimethyl pyrrole ring from the acetamido group. In the final step, after treatment with hydroxylamine dihydrochloride, the pyrrole ring is removed and a free amino group is regenerated.


📜 SIMILAR VOLUMES


ChemInform Abstract: Synthesis of Novel
✍ Zita Puterova; Tomas Bobula; Daniel Vegh 📂 Article 📅 2008 🏛 John Wiley and Sons ⚖ 26 KB 👁 1 views

## Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable v

Improved synthesis of 5-hydroxymethyl-2′
✍ Anders S. Hansen; Armin Thalhammer; Afaf H. El-Sagheer; Tom Brown; Christopher J 📂 Article 📅 2011 🏛 Elsevier Science 🌐 English ⚖ 436 KB

a b s t r a c t 5-Hydroxymethylcytosine has recently been characterized as the 'sixth base' in human DNA. To enable research on this DNA modification, we report an improved method for the synthesis of 5-hydroxymethyl-2 0 -deoxycytidine ( 5-HOMe dC) phosphoramidite for site-specific incorporation int