- A 4 - chloro methyl -5 - methyl - 1, 3 - dioxo heterocyclic pentene -2 - one purification method
-
The invention discloses a purification method of 4-chloromethyl-5-methyl-1,3-dioxole-2-ketone. The purification method comprises the following steps of dissolving a crude product of 4-chloromethyl group-5-methyl-1,3-dioxole-2-ketone into a mixed solvent of methyl alcohol, ethyl alcohol, isopropyl alcohol and tertiary butanol for crystallizing for 0-24 hours at a temperature of -10-0 DEG C, and filtering to acquire the 4-chloromethyl-5-methyl-1,3-dioxole-2-ketone. The purification method has the characteristics of low cost, good refining effect, high yield, low requirement on equipment and simplicity and convenience in operation and is suitable for industrial production.
- -
-
Paragraph 0023-0050
(2019/03/21)
-
- Synthetic method of 4-chloromethyl-5-methyl-1,3-dioxole-2-ketone
-
The invention relates to a synthetic method of 4-chloromethyl-5-methyl-1,3-dioxole-2-ketone. The method comprises the following steps that 1, DMDO is dissolved in organic solvent, and heating reflux is conducted, wherein the mass-to-volume ratio of the DMDO to the organic solvent ranges from 1:5 to 1:9; 2, by keeping a reflux state, sulfonyl chloride is evenly and dropwise added within 1-4 h, after the sulfonyl chloride is dropwise added, heat preservation is conducted continuously for 2 h to enable the reaction to be completely conducted, wherein the mole ratio of the DMDO to the sulfonyl chloride ranges from 1:0.7 to 1:3.5; 3, after the reaction is completed, rotary evaporateion is conducted to remove the organic solvent; 4, solid free radical scavenger is added, the temperature is raised to 90 DEG C, rearrangement is conducted, and a crude product of 4-chloromethyl-5-methyl-1,3-dioxole-2-ketone is obtained, wherein the dosage of the solid free radical scavenger is 0.5%-2% of the mass of the DMDO; 5, under the vacuum degree of 2 mmHg, distillation is conducted at the temperature ranging from 91 DEG C to 93 DEG C, and high-purity 4-chloromethyl-5-methyl-1,3-dioxole-2-ketone is obtained. According to the synthetic method of the 4-chloromethyl-5-methyl-1,3-dioxole-2-ketone, the conversion efficiency of the product and the yield of a target product can be improved, the production cost is reduced, and good economic benefit is achieved.
- -
-
Paragraph 0002; 0016; 0017
(2016/10/07)
-
- A Convenient and Practical Preparation of 4-Chloromethyl-5-methyl-1,3-dioxol-2-one
-
A new synthetic method for 4-chloromethyl-5-methyl-1,3-dioxol-2-one (1c), which is useful for preparing prodrugs, has been developed.Ene-chlorination of 4,5-dimethyl-1,3-dioxol-2-one (2) with chlorine or sulfuryl chloride afforded 4-chloro-4-methyl-5-methylene-1,3-dioxolan-2-one (3) in good yield.Compound 3 underwent allylic rearrangement to afford 1c quantitatively.The overall yield of 1c from 2 was approximately 80percent. Keywords---4-chloromethyl-5-methyl-1,3-dioxol-2-one; 4,5-dimethyl-1,3-dioxol-2-one; 4-chloro-4-methyl-5-methylene-1,3-dioxolan-2-one; ene-chlorination; allylic rearrangement; (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl group; promoiety; prodrug
- Ikeda, Shoji,Takebe, Yasushi,Hirayama, Ryoichi,Sakamoto, Fumio,Iuchi, Koji,Tsukamoto, Goro
-
p. 394 - 397
(2007/10/02)
-
- 4-Chloro-4-methyl-5-methylene-1,3-dioxolane-2-one
-
4-Chloro-4-methyl-5-methylene-1,3-dioxolane-2-one is useful as an intermediate for the synthesis of 4-chloromethyl-5-methyl-1,3-dioxolene-2-one which, in turn, finds use as a modifying agent for making various prodrugs. Said intermediate compound gives said objective compound in a good yield by a rearrangement reaction.
- -
-
-