1st publication: on the short report “A One-Pot Domino Synthesis of 5-(Trifluoromethyl)-2-thiazolamine”, by Xue-fei Bao, Xue-jun Qiao, Xiao Hou, Wu-hong Fang, Xue-long Liu and Guo-liang Chen, published in the Journal of the Brazilian Chemical Society, Vol. 27, No. 12, 2388-2391, 2016 (http://dx.doi.org/10.5935/0103-5053.20160132):
Title:
Where it reads 5-(Trifluoromethyl)-2-thiazolamine
Should be read 4-(trifluoromethyl)-2-thiazolamine
Abstract:
Where it reads 5-(Trifluoromethyl)-2-thiazolamine
Should be read 4-(trifluoromethyl)-2-thiazolamine
Keywords:
Where it reads 5-(trifluoromethyl)-2-thiazolamine
Should be read 4-(trifluoromethyl)-2-thiazolamine
Scheme 1:
Where it reads The synthesis of 5-(trifluoromethyl)-2-thiazolamine.
Should be read The synthesis of 4-(trifluoromethyl)-2-thiazolamine.
Page 2388, 2389:
Where it reads 5-(trifluoromethyl)-2-thiazolamine
Should be read 4-(trifluoromethyl)-2-thiazolamine
Tables 1 and 2:
Where it reads aIsolated yield of 5-(trifluoromethyl)-2-thiazolamine.
Should be read aIsolated yield of 4-(trifluoromethyl)-2-thiazolamine
Scheme 2:
Where it reads
Should be read
Page 2390:
Where it reads
A plausible mechanism for cyclization reaction is shown in Scheme 2. Cyanamide 4 deprotonates into its anion 5 via hydrogen abstraction reaction by the base. Successively, a nucleophilic substitution reaction with 3 gives carbodiimide intermediate 6, which becomes prone to attack due to keto-enol tautomerism forming tautomer 7 and the attack takes place on the carbon of the carbodiimide producing anion 8. Finally, compound 8 abstracts a hydrogen from conjugate acid to furnish the desired compound 5-(trifluoromethyl)- 2-thiazolamine (1) and regenerate the base.
Should be read
A plausible mechanism for cyclization reaction is shown in Scheme 2. 3-Bromo-1,1,1-trifluoropropane-2-thione 3 deprotonates and then offered the intermediate 5 via a process similar to Hoffmann rearrangement. Successively, intermediate 5 is added with cyanamide after deprotonation to form intermediate 6. Then the intermediate 7 is obtained by intramolecular cyclization. Finally, 7 abstracts a hydrogen from conjugate acid to furnish the desired compound 4-(trifluoromethyl)-2-thiazolamine 1 and regenerate the base.
Conclusions:
Where it reads 5-(trifluoromethyl)-2-thiazolamine
Should be read 4-(trifluoromethyl)-2-thiazolamine
Publication Dates
-
Publication in this collection
26 May 2023 -
Date of issue
2023
