. Hz, ), 4H), 3.74 (dqd, J = 12.5, 6.3, 2.4 Hz4H) 1H), 2.53 (s, 1.8H), 2.52 (s, 1.2H), 2.25-2.12 (m, 1H), 2.05 (ddd, pp.6-9438

1. Hz, 03 (ddd, J = 14.2, 12.1, 3.9 Hz, 1H); 13 C NMR (100 MHz; CDCl 3 ): ? C major diastereoisomer: 164, 1H), 3.15 (s, 3H), 2.39 (ddd, J = 13.8, 11.3, 2.4 Hz, 1H), pp.92-320, 1131.

1. Hz, 68 (s, 3H), 3.32-2.13 (m, 2H); 13 C NMR (100 MHz; CDCl 3 ): ? C major diastereoisomer: 169, dd, J = 12.2, 5.9 Hz, 1H), 3.69-3.58 (m, 1H) Hz), 123.8 (q, J = 279 Hz), 123.3 (d, J = 5 Hz) (d, J = 239 Hz), 153.8 (d, J = 17 Hz), 136.9 (d, J = 9 Hz), 123.8 (q, J = 279 Hz), pp.58-61, 1132.

. Hz, 78 (m, 0.35H), 3.78-3, pp.4-33

C. Nmr, CDCl 3 ): ? C 157.1 (t, J = 288 Hz, 55.3, 39.7 (t, J = 2 Hz), 1166.

1. Hz, 32-2.13 (m, 2H); 13 C NMR (100 MHz; CDCl 3 ): ? C 171, 1H), 3.47-3.40 (m, 1H), 2.77- 2.64 (m, 2H)EI + ): calculated (found) for C 12 H 9, p.82, 1317.

1. Hz, 94- 1.84 (m, 1H), 1.83- 1.74 (m, 1H); 13 C NMR (100 MHz; CDCl 3 ): ? C 162, pp.44-47

. Hz, d, J = 4 Hz), 25.0; IR (CCl 4 ): ? HRMS (EI + ): calculated (found, 1224.

. Dimethyl, 5-difluoropent-4-en-1-yl)phosphonate (14h) Following general procedure C with 13a (150 mg, 0.57 mmol) The residue was purified by silica gel column chromatography, DCM/methanol 95:5) to afford 14h (98 mg, 80%) as a colorless oil

J. =. Dtd, 73 (s, 3H), 3.70 (s, 3H), 2.13- 1.98 (m, 2H), 1.79-1.59 (m, 4H); 13 C NMR (100 MHz; CDCl 3 ): ? C 156.6 (t, J = 287 Hz), NMR (400 MHz 52.3 (d, J = 6 Hz, 2C) HRMS (EI + ): calculated (found), pp.9-76, 1036.

. Hz, 13 C NMR (100 MHz; CDCl 3 ): ? C 173.2, 156.1 (t, J = 285 Hz), 2C, vol.17, issue.221, pp.40-41

J. Hzq, . =277-hzq, and . Hz, 13 C NMR (100 MHz; CDCl 3 ): ? C major isomer: 137.6, 121.7, 104.1, 77.2 (2C) 122.5, 99.4, pp.2275-983, 1016.

J. Ichikawa, H. Fukui, Y. L. Ishibashi, S. Z. Zard, S. Z. Zard et al., 17 For reviews, see: (a) Zard, S, Tetrahedron Lett. J. Org. Chem. Tetrahedron Lett. Z. Angew. Chem., Int. Ed. Engl, vol.39, issue.36, pp.587-455, 1997.

B. Sire, (e) For an account of the discovery of this process, see: Zard, S (f) For applications to the synthesis of heteroaromatics, see: El Qacemi, Pure Appl. Chem. Z. Aust. J. Chem, vol.83, issue.59, pp.519-663, 2006.

S. Z. Zard, For the synthesis of organofluorine compounds, see: (g) Bertrand, Org. Biomol. Chem, vol.2012, issue.10, p.5707