(guanfacin$ or Afken or Estulic
Chemical Name: N-amidino-2-(2,6dichlorophenyl) acetamide monohydrochloride
(CAS NO.: ), with its systematic name of acetamide, N-(aminoiminomethyl)-2,6-dichloro-, monohydrochloride, could be produced through many synthetic methods.
Following are some of the synthesis routes:
Method one:
1). By methanolysis of 2,6-dichlorophenylacetonitrile (I) in the presence of H2SO4 to methyl 2,6-dichlorophenylacetate (II), which is then condensed with guanidine (A) in isopropanol.
2). By condensation of S-methylisothiourea (V) with 2,6-dichlorophenylacetyl chloride (VI) in acetone to afford S-methyl-N-(2,6-dichlorophenylacetyl)isothiourea (VII); this product is then treated with ammonia in isopropanol.
3). By condensation of 2,6-dichlorophenylacetic acid (VIII) with guanidine (A) in toluene.
![](https://www.lookchem.com/UserFilesUpload/Systematic%20Method%20of%20Guanfacine%20hydrochloride1.jpg)
EXAMPLE 4 2,6-dichlorophenyl-acetyl-guanidine hydrochloride A solution of 65.7 g. (0.3 moles) of 2,6-dichlorophenylacetic acid methyl ester (B.P. 149 C./ 17 mm. of Hg) in 200 cc. of isopropanol is added to a solution of 19.5 g. (0.33 moles) of guanidine in 150 cc. of isopropanol. The resulting reaction mixture is stirred for 15 minutes and is then concentrated by evaporation in a vacuum. The resulting white residue, consisting of 2,6-dichlorophenylacetyl-guanidine, is suspended in 100 cc. of isopropanol, whereupon acidification is effected with ethanolic hydrochloric acid. The resulting precipitate is crystallized from isopropanol/ethanol and recrystallized from ethanol. 2,6 dichlorophenyl acetyl guanidine hydrochloride is obtained in the form of white needles having a melting point of 215-217 C.
making the 2,6-dichlorophenylacetic acid methyl ester would be easy I think.
will add an OTC route to this in my book