Thionation ofω-Acylamino Ketones withLawesson's Reagent: Convenient Synthesis of 1,3-Thiazoles and 4H-1,3-Thiazines
摘要:
The reaction of omega -acylamino ketones with Lawesson's reagent (=2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide; LR) is described. Treatment of 2-acylamino ketones 1 (n = 0) with LR gave 1,3-thiazole derivatives 3 in good yields (Scheme I and Table 1). The 4H-1,3-thiazines 4 were obtained as main products by treatment of 3-acylamino ketones 2 (n = 1) with an equimolar amount of LR, while mainly the corresponding 3-(thioacyl)amino ketones 5 were isolated when 0.5 equiv. of LR was used. The 3-acylamino esters 7 also reacted with LR to give the corresponding 3-(thioacyl)amino esters 8 (Scheme 3 and Table 2).
Amidoacetone enolate anions: alkylation and Michael reaction
作者:Thomas R. Hoye、Steven R. Duff、Rita S. King
DOI:10.1016/s0040-4039(00)98657-x
日期:1985.1
The lithium enolate derived from benzamidoacetone (1) can be regiospecifically alkylated at C(1) and stereospecifically added in conjugate fashion to cyclohexenone without resorting to protection of the free NH. Comparison is made with alkylations of methyl hippurate.