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ChemicalBook CAS DataBase List 5-PYRIDIN-3-YL-[1,3,4]THIADIAZOL-2-YLAMINE
68787-52-0

5-PYRIDIN-3-YL-[1,3,4]THIADIAZOL-2-YLAMINE synthesis

15synthesis methods
-

Yield:68787-52-0 95%

Reaction Conditions:

Stage #1: nicotinoyl thiosemicarbazidewith sulfuric acid at 100; for 3 h;
Stage #2: with sodium hydroxide in water at 23; pH=Ca.9;

Steps:

2 Example 2
Preparation of 2-amino-5-(3-pyridyl)-1,3,4-thiadiazole

A mixture of the thiosemicarbazide (1.01 g, 4.34 mmol) in 5 mL of concentrated sulfuric acid was heated to 100° C. for 3 h.
The reaction mixture was cooled to 23° C. and a 50% aqueous solution of sodium hydroxide was added until pH≈9.
The solid was collected, washed with water, and air dried to give 620 mg of 2-amino-5-(3-pyridyl)-1,3,4-thiadiazole.
The filtrate was extracted with ethyl acetate.
The ethyl acetate extracts were combined, dried over MgSO4, and concentrated to dryness to give 0.120 g of 2-amino-5-(3-pyridyl)-1,3,4-thiadiazole.
The lots were combined to give (0.738 g, 95%) of 2-amino-5-(3-pyridyl)-1,3,4-thiadiazole: 1H NMR (300 MHz, DMSO-d6) δ 8.9 (d, 1H), 8.6 (dd, 1H), 8.1 (td, 1H), 7.57 (s, 2H), 7.5 (m, 1H).

References:

US2012/53146,2012,A1 Location in patent:Paragraph 0093; 0094

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