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Method of Making Cis-1-chloro-3,3,3-trifluoropropene Disclosure Number: IPCOM000236553D
Publication Date: 2014-May-02
Document File: 4 page(s) / 40K

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The Prior Art Database


The present invention relates to the preparation of unsaturated fluoro-alkenes, more specifically, 1-chloro-3,3,3-trifluoropropene (1233zd), even more particularly, Cis-1-chloro-3,3,3-trifluoropropene (cis-1233zd).

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Method of Making Cis-1-chloro-3,3,3-trifluoropropene

Field of the invention

The present invention relates to the preparation of unsaturated fluoro-alkenes, more specifically, 1-chloro-3,3,3-trifluoropropene (1233zd), even more particularly, Cis-1- chloro-3,3,3-trifluoropropene (cis-1233zd).

Problem to be solved

Both cis and trans isomers have practical applications, and the cis-1233zd is more suitable for solvent applications than its trans isomer because of its higher boiling point. There are various methods of making 1233zd (US 6958424, US 6844475, US 5616819, US 2008/0103342, WO 2010/059496), but the trans-1233zd is the predominant product with only 3-5% of cis isomer isomer in the manufacturing process. The disclosure of H0031384 and H0031385 have developed a process of making cis-1233zd from 1,1,2- trichloro-3,3,3-trifluoropropane (233da) with zinc in water, which gives about 40% of cis isomer. However, this process will generate tons of zinc waste on industrial scale, which is difficult to get rid of. WO 2010/068715 discribed a process using fluorinated Cr2O3 isomerization of trans-1233zd at 300°C to give about 10% cis isomer combined with 2- 3% of other heavier materials. Thus there is a need for a process which makes 1233zd wherein a substantial portion of cis isomer is present or even more preferably, stereospecifically produce cis-1233zd.

Back Ground of the Invention

Alkynes could be halogenated with SbCl5 (J. Chem. Soc., 1979, 548; J. Chem. Soc., comm., 1976, 4, 145) CuCl2-LiCl (J. Chem. Soc., 1977, 676) and HgX2 (J. Chem. Soc. Perkin Trans 1, 1987, 1017) to give a mixture of cis and trans halogenated alkenes. Cousseau at el reported hydrogen chloride addition to alkynes under Lewis acid catalyst (J. Chem. Soc. Perkin Trans 1, 1977, 1797). Recently, Yu reported hydrogen chloride reaction with acetylene in ionic liquid [Bmim]Cl under catalyst CuCl to give quantitative chloroethylene (WO20110050614).

A previous work used 3,3,3-trifluoropropyne reacting with HCl to give a product, which reported a boiling point of 21°C (J. Chem. Soc., 1952, 3490). It is close to the boiling point of trans-1233zd (18.7°C). However, this reaction is not reproducible under the author described conditions. US8404907 described a process of reduction 1-chloro-3,3,3- trifluoropropyne with palladium under hydrogen atmosphere to stereospecifically generate cis-1233zd in 53% yield. However, over reduction occurred inevitably to give CF3CH=CH2 and CF3CH2CH3. The application 61/567665 described a process with metal catalysts such as cupreous chloride (CuCl2, SbCl5, ZnCl2, AlCl3, FeCl3, etc) at elevated temperature of 50-200°C to stereoselectively produce cis-1233zd. This reaction provided a unique way of making cis-1233zd. However, some side products were detected, especially, 1233xf, which was very difficult to separate from cis-1233zd.

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Detailed Disclosure

Chlorofluorocarbons (CFCs) are known and widely used in...