Title:
PROCESS OF PREPARING DIAZOMETHANE
Document Type and Number:
WIPO Patent Application WO/2020/232625
Kind Code:
A1
Abstract:
The present invention provides a process of preparing diazomethane. The process comprises: step S1, using N-methylurea as a raw material to continuously prepare a first product system containing N-methyl-N-nitrosourea in a continuous reactor; step S2, extracting and back-extracting the first product system continuously to obtain a N-methyl-N-nitrosourea solution; step S3, continuously reacting the N-methyl-N-nitrosourea solution with an alkali solution in a continuous reactor to obtain a second product system containing diazomethane; and step S4, continuously performing liquid separation and water removal by freezing on the second product system to obtain the diazomethane. A 2-methyltetrahydrofuran solution of MNU is obtained through a completely continuous reaction and posttreatment by using N-methylurea as a raw material, and then an anhydrous diazomethane solution is directly obtained through a completely continuous reaction and posttreatment. Water is removed by a freezing technology, and use of an expensive semipermeable membrane or liquid-liquid separator is avoided, so that the cost is lower.
Inventors:
HONG HAO (US)
LU JIANGPING (CN)
ZHANG ENXUAN (CN)
SHEN WEI (CN)
YAN HONGLEI (CN)
ZHANG ZHEN (CN)
LU JIANGPING (CN)
ZHANG ENXUAN (CN)
SHEN WEI (CN)
YAN HONGLEI (CN)
ZHANG ZHEN (CN)
Application Number:
PCT/CN2019/087761
Publication Date:
November 26, 2020
Filing Date:
May 21, 2019
Export Citation:
Assignee:
ASYMCHEM LAB TIANJIN CO LTD (CN)
International Classes:
C07C245/16; C07C245/14
Foreign References:
| US5854405A | 1998-12-29 | |||
| CN105418452A | 2016-03-23 | |||
| US5459243A | 1995-10-17 | |||
| US5854405A | 1998-12-29 | |||
| EP0916649A1 | 1999-05-19 | |||
| CN101844063A | 2010-09-29 |
Other References:
ORG. PROCESS RES. DEV., vol. 6, 2002, pages 884
ORGANIC PROCESS RESEARCH & DEVELOPMENT, vol. 16, no. 5, 2017, pages 1146 - 1149
MAURYA RA ET AL.: "report that a dual-channel coil reactor with a polydimethylsiloxane (PMDS) semipermeable membrane is used to prepare and separate a diazomethane gas for a reaction", SYNTHETIC COMMUNICATIONS, vol. 46, no. 1, 2016, pages 55 - 62
MASTRONARDI F ET AL.: "report a process of using an AF-2400 material as a semipermeable membrane tube in tube with Diazald as a raw material for continuous production and reaction of diazomethane", ORGANIC LETTERS, vol. 15, no. 21, 2013, pages 5590 - 5593
DALLINGER D ET AL.: "also report a process of using an AF-2400 material as a semipermeable tube in flask with Diazald as a raw material for continuous preparation and reaction of diazomethane", JOURNAL OF ORGANIC CHEMISTRY, vol. 81, no. 14, 2016, pages 5814 - 5823
LEHMANN H ET AL.: "use a PFA coil and a liquid-liquid separator with a semipermeable membrane structure and use N-methylurea as a raw material, to achieve a two-step full continuous reaction of diazomethane precursor MNU and diazomethane", GREEN CHEMISTRY, vol. 19, no. 6, 2016, pages 1449
See also references of EP 3974411A4
ORGANIC PROCESS RESEARCH & DEVELOPMENT, vol. 16, no. 5, 2017, pages 1146 - 1149
MAURYA RA ET AL.: "report that a dual-channel coil reactor with a polydimethylsiloxane (PMDS) semipermeable membrane is used to prepare and separate a diazomethane gas for a reaction", SYNTHETIC COMMUNICATIONS, vol. 46, no. 1, 2016, pages 55 - 62
MASTRONARDI F ET AL.: "report a process of using an AF-2400 material as a semipermeable membrane tube in tube with Diazald as a raw material for continuous production and reaction of diazomethane", ORGANIC LETTERS, vol. 15, no. 21, 2013, pages 5590 - 5593
DALLINGER D ET AL.: "also report a process of using an AF-2400 material as a semipermeable tube in flask with Diazald as a raw material for continuous preparation and reaction of diazomethane", JOURNAL OF ORGANIC CHEMISTRY, vol. 81, no. 14, 2016, pages 5814 - 5823
LEHMANN H ET AL.: "use a PFA coil and a liquid-liquid separator with a semipermeable membrane structure and use N-methylurea as a raw material, to achieve a two-step full continuous reaction of diazomethane precursor MNU and diazomethane", GREEN CHEMISTRY, vol. 19, no. 6, 2016, pages 1449
See also references of EP 3974411A4
Attorney, Agent or Firm:
KANGXIN PARTNERS, P. C. (CN)
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