CC BY 4.0 · Pharmaceutical Fronts 2020; 02(03): e128-e132
DOI: 10.1055/s-0040-1722215
Original Article

Continuous-Flow Processes for the Production of Floxacin Intermediates: Efficient C–C Bond Formation through a Rapid and Strong Activation of Carboxylic Acids

Shao-Zheng Guo
1   College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing 312000, People's Republic of China
,
Zhi-Qun Yu
2   Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
,
Wei-Ke Su
2   Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
› Author Affiliations
Funding We are grateful to the Public Projects of Zhejiang Province (Grant No. 2016C33071) and the National Natural Science Foundation of China (Grant No. 21676252 and 21406203) for financial support.

Abstract

The development of highly efficient C–C bond formation methods for the synthesis of ethyl 2-(2,4-dichloro-5-fluorobenzoyl)-3-(dimethylamino)acrylate 1 in continuous flow processes has been described, which is based on the concept of rapid and efficient activation of carboxylic acid. 2,4-Dichloro-5-fluorobenzoic acid is rapidly converted into highly reactive 2,4-dichloro-5-fluorobenzoyl chloride by treating with inexpensive and less-toxic solid bis(trichloromethyl)carbonate. And then it rapidly reacts with ethyl 3-(dimethylamino)acrylate to afford the desired 1. This process can be performed under mild conditions. Compared with the traditional tank reactor process, less raw material consumption, higher product yield, less reaction time, higher operation safety ensured by more the environmentally friendly procedure, and process continuity are achieved in the continuous-flow system.



Publication History

Article published online:
31 December 2020

© 2020. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/)

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  • References

  • 1 Fernández J, Navasa M, Gómez J. et al. Bacterial infections in cirrhosis: epidemiological changes with invasive procedures and norfloxacin prophylaxis. Hepatology 2002; 35 (01) 140-148
  • 2 Tutkun A. Ciprofloxacin. Arch Otolaryngol Head Neck Surg 1994; 120 (08) 886
  • 3 Mahajan PM, Jadhav VH, Mehta JM. Pefloxacin in histoid leprosy. Int J Lepr Other Mycobact Dis 1994; 62 (02) 297-298
  • 4 Stuck AE, Kim DK, Frey FJ. Fleroxacin clinical pharmacokinetics. Clin Pharmacokinet 1992; 22 (02) 116-131
  • 5 Wen XM, Chen MR, Wang Y, Wang HS, Liu J, Sun QS. Synthesis of 2,4-dichloro-5-fluorobenzoyl chloriedas Intermediate of ciproflxacin. J Ji Ning Med College 2000; 23 (02) 21-22
  • 6 Zhang YZ, Yu HJ. Synthesis of 2,4-dichloro-5-fluorobenzoic acid [in Chinese]. Liaoning Chem Industry 1993; 6: 37-38
  • 7 Schwalbe T, Kadzimirsz D, Jas G. Synthesis of a library of ciprofloxacin analogues by means of sequential organic synthesis in microreactors. QSAR Comb Sci 2005; 24 (06) 758-768
  • 8 Ralf P. Process for the preparation of halogenated benzoic acid by xoidation of benzophenones. EP Patent 600317. November, 1992
  • 9 Shi YJ, Zhang HX, Xu YR. et al. Synthesis of 2, 4-dichloro-5-fluorobenzoic acid. CN Patent 1031074. February, 1989
  • 10 Cavani F, Centi G, Perathoner S, Trifir F. Sustainable industrial chemistry. Vch Pub 2009; 439-448
  • 11 Babad H, Zeiler AG. Chemistry of phosgene. Chem Rev 1973; 73: 75-91
  • 12 Eckert H, Forster B. Triphosgene, a crystalline phosgene substitute. Angew Chem Int Ed Engl 1987; 26 (09) 894-895
  • 13 Cotarca IL, Bacaloglu IR, Csunderlik C, Marcu IN, Tarnaveanu IA. Nucleophile Substitutionen an Kohlensurederivaten. XX. Aminolyse des Bis(trichlormethyl)carbonates. Adv Synth Catal 1987; 329 (06) 1052-1062
  • 14 Cotarca L, Bacaloglu R, Marcu N, Târnaveanu A. Nucleophile Substitutionen an Kohlensäurederivaten. XIX. Alkoholyse und Hydrolyse des Bis(trichlormethyl)carbonates. J Prakt Chem 1985; 327 (06) 881-886
  • 15 Fuse S, Tanabe N, Takahashi T. Continuous in situ generation and reaction of phosgene in a microflow system. Chem Commun (Camb) 2011; 47 (47) 12661-12663
  • 16 Fuse S, Mifune Y, Takahashi T. Efficient amide bond formation through a rapid and strong activation of carboxylic acids in a microflow reactor. Angew Chem Int Ed Engl 2014; 53 (03) 851-855
  • 17 Battilocchio C, Deadman BJ, Nikbin N, Kitching MO, Baxendale IR, Ley SV. A machine-assisted flow synthesis of SR48692: a probe for the investigation of neurotensin receptor-1. Chemistry 2013; 19 (24) 7917-7930
  • 18 Yu ZQ, Lv YW, Yu CM, Su WKA. A high-output, continuous selective and heterogeneous nitration of p-difluorobenzene. Org Process Res Dev 2013; 17 (03) 438-422
  • 19 Xu J, Yu J, Jin Y, Li J, Yu Z, Lv Y. A continuous flow microwave-assisted fischer indole synthesis of 7-ethyltryptophol. Chem Eng Process 2017; 121: 144-148
  • 20 Yu ZQ, Lv YW, Yu CM. A continuous kilogram-scale process for the manufacture of o-difluorobenzene. Org Process Res Dev 2012; 16 (10) 1669-1672
  • 21 Lv YW, Yu ZQ, Su WK. A continuous kilogram-scale process for the manufacture of 7-ethyltryptophol. Org Process Res Dev 2011; 15 (02) 471-475
  • 22 Cotarca L, Geller T, Répási J. Bis(trichloromethyl)carbonate (BTC, triphosgene): a safer alternative to phosgene?. Org Process Res Dev 2017; 21 (09) 1439-1446