1,4-Dioxane → HCID 10198962, compound

Participants

Reaction Steps

To a solution of the diamine of Step A (4.16 g) in dioxane (110 mL) was added under nitrogen 1,1′-thiocarbonyl-di-1,2,4-triazole (7.12 g). After 30 minutes, para-toluenesulfonic acid monohydrate (15.1 g) was added and the reaction mixture was heated at reflux for 20 hours. More para-toluenesulfonic acid monohydrate (4.0 g) was added at this point, and after an additional 2.5 hours at reflux, the reaction was cooled and filtered. The filtrate was concentrated in vacuo to give an orange oil. The crude material was dissolved in dichloromethane and absorbed onto a column of Merck-60 flash silica gel. Elution with 20% ethyl acetate in hexane provided a white solid which was triturated with diethyl ether to give the title product (2.0 g, 40.3%) as a white solid, m.p. 164-165° C.

Provenance & Evidence