A practical way to synthesize chiral fluoro-containing polyhydro-2H-chromenes from monoterpenoids

• Oksana S. Mikhalchenko,
• Dina V. Korchagina,
• Konstantin P. Volcho and
• Nariman F. Salakhutdinov

Beilstein J. Org. Chem. 2016, 12, 648–653, doi:10.3762/bjoc.12.64

• was 7% (Table 2). Thus, we found for the first time the conditions enabling production of chiral fluoro-containing heterocyclic compounds from a monoterpenoid using the halo-Prins cyclisation. It should also be noted that preparative isolation of compounds of type 7a is complicated by the presence of

• as fluorine sources. Presumably, the reaction starts with the Prins cyclisation resulting in the formation of cation 10. There are then several mechanistic pathways, some or all of them may be in operation: a) cation 10 may undergo stereoselective trap by [F−] to form fluoride epimers 8; b) cation 10

Prins fluorination cyclisations: Preparation of 4-fluoro-pyran and -piperidine heterocycles

• Guillaume G. Launay,
• Alexandra M. Z. Slawin and
• David O'Hagan

Beilstein J. Org. Chem. 2010, 6, No. 41, doi:10.3762/bjoc.6.41

• . Keywords: 4-fluoropiperidine; 4-fluoropyran; heterocycles; organo-fluorine chemistry; Prins cyclisation; Introduction Selective incorporation of the C–F bond into organic molecules can impart useful and attractive properties to performance materials [1][2][3]. To this end there are a useful but relatively