Fluorinated indolizines

Fluorinated Indolizines, Indolizidines, Indoles, and Related Compounds... 

In a similar approach, Huang and coworkers pubhshed a series of papers describing the cycloaddition reactions of fluorinated olefins, generated in situ from fluorinated alkanoates, with pyridinium and other nitrogen-based ylides. The synthesis of the fluorinated indolizine 76 that proceeds by cycloaddition followed by a dehydrochlorination step provides an example of this chemistry (Fig. 3.35). ... 

FIGURE 3.35 Nitrogen-based ylides in the preparation of fluorinated indolizines. 

FIGURE 3.36 Pyridinium ylides as precursors of fluorinated indolizines. 

FIGURE 3.37 Further examples of nitrogen-based ylides in the s)mthesis of fluorinated indolizines and related structures. 

Wu, K. Chen, Q.-Y. S3mthesis of fluorinated indolizines and 4//-pyrrolo[l,2-fl]henzi-midazoles via 1,3-dipolar cycloaddition of fluoroalkenes to iV-ylides. Synthesis 2003, 35 0. 

Wu K, Chen QY (2003) Synthesis of fluorinated indolizines and 4H-pyrrolo [1,2-a] benzimidazoles via 1,3-dipolar cycloaddition of fluoroalkenes to N-yUdes. Synthesis 29-32... 

In the presence of K2CO3 and EtsN, pyridinium N-ylides, generated in situ from their halides, reacted with gaseous fluoroalkenes CF2=CFX (X=C1, Br) in DMF under atmospheric pressure in normal glassware at 70 °C to give the corresponding 1,2-fluorinated indolizines. Similar results were obtained with tetrafluoroethene in an autoclave [30],... 

Fluorinated indolizines remained relatively rare class of compounds. In contrast to indolizines substituted at pyrrole fragment the structures having a perfluoro-substituent in the pyridine ring are less available. This is caused by the fact that 3... 

Banks RE, Khaffaff SN (1991) Fluorocarbon derivatives of nitrogen. Part 18. Synthesis of fluorinated indolizines through reactions of pyridinium ethoxycarbonylmethyUde or pyridin-ium phenacyUde with perfluoropropene, perfluorobut-2-yne and 3,3,3-trifluoro-propyne. J HuorChem 3 407- 18... 

Banks RE, Thomson J (1985) Reaction of pyridinium t-butoxycarbonylmethylide with perfluoropropene and with some fluoroaromatic compounds synthesis of some fluorinated indolizines. J Chem Res Miniprint 2 671-689... 

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