Science of Synthesis

Hashmi, A. S. K., Science of Synthesis, (2008) 32, 24.

For fluoro compounds the methods of preparation range from photochemical reactions,[‌12‌] zinc-induced 1,2-elimination,[‌13‌,‌14‌] elimination of selenium oxides,[‌15‌] SN2′-replacement[‌16‌] or a combination of SN2-replacement/base-catalyzed rearrangement,[‌17‌] and electrophilic addition to 1,3-enynes.[‌18‌] While these publications do not include detailed experimental procedures, an interesting sequence of an SN2′-replacement and an SN2-type replacement by organocuprates allows the selective synthesis of even tetrasubstituted fluoroallenes ‌5‌ (‌Scheme 2‌). Under properly controlled reaction conditions, the difluoroallenes ‌4‌ can be obtained from the starting material ‌3‌.[‌19‌] This method tolerates benzyl-protected alcohols and acetal-protected aldehyde groups.

‌Meeeee 8‌ Meeeeeeee Meeeeeeee ee Meeeeeeeeeeee eee 8,8-Meeeeeeeeeeeeee Meeee Meeeeeeeeeeeee[‌88‌]

Meeeeeeeeeee Meeeeeeee

8-[8-(8,8-Meeeee-8-ee)eeeee]-8,8-eeeeeeee-8-eeeeeeeeeee-8,8-eeeee [‌8‌, M8 = 8-(8,8-Meeeee-8-ee)eeeee]; Meeeeee Meeeeeeee:[‌88‌]

Me (888 ee, 88.8 eeee) eee eeeeeeeee ee eeee eee eeeee eeeeeee eeeeeeee. Me eee eeeeee ee e eeeee-eeeeeeee eeeee, eeeeeeee eeee e eeeeeeeee, eeeee eeeee, eee MMM (88 eM) eee eeeee. Meeee e eeeeeee, e eeee ee 8-(8-eeeeeeeeee)-8,8-eeeeeee (88.8 eeee) ee MMM (88 eM) eee eeeee eeeeeeee. Meeeee eee eeeeeee eeeeeeee, eee eeeeeee eee eeeeee eeeee ee eeeeeee ee eeeee eee eeeeeeeee eeee ee eeee. Mee eeeeeeee eee eeeeeeee ee 8 e, eeeeee e eeee ee 8-(8,8-eeeeee-8-ee)eeeeeeeeeeeeee eeeeeee. Me eeeeeeeee eee eeeeeeee ee eee eeee, eee Meeeeeee eeeeeee (8.8 eM), M8M (88 eM), eee eeeeeeeeeeeeeee (8 eeeee) eeee eeeeee ee ee Meeeeeeeee eeeee. 8.8 M ee MMe eee eeeee eeeeeeee eeeee eee eeee eeeeee eeeee. Mee eeee eeeeeeeee eee eeee 8 eeeee eee eee eeeeeee eee eeeeeeee.

M 88-eM, eeeee-eeeeee eeeee-eeeeeeee eeeee eeeeeeeeee MeMe (888 ee, 8 eeee) eee eeeeeee eeee eee MMM (88 eM) eee eeeeee ee −88°M. Me eeee eeeeeee eee eeeee e eeee ee 8-(8,8-eeeeee-8-ee)eeeeeeeeeeeeee eeeeeee ee MMM (8.8 eeee; eeeeeeee ee eeeee) eee eee eeeeeee eee eeeeeee eee 8 eee. Mee eeeeeeeee eeeeeeeeeeee eeeeeee eeee eee eeeeee ee −88°M eeeeeeeeeee eee eeeeee ‌8‌ eee eeeee eeeee eee eeee ee eee eeeee eeeee eeeeeee eee eeeeeeeeeee ee −88°M. Meeee eeeeeeee eee 8 e ee −88°M, eee eeeeeee eee eeeeee eeee ee MM8Me ee eee ee eeeeee eee eeeeeeee. Mee eeeeeee eeeee eee eeeeeeeee eeee eeee eeeeee (8 × 88 eM). Meeee eeeeee eee eeeeeeee eeeeeee eeee (Me8MM8), eee eeeeeeee eeee eeeeeee eeeee eeeeeee eeeeeeee. Meeeee/MeMMe (8:8) eee eeee eee eeeeee eeeeeeeeeeeeee. Mee eeeeeee eee e eeeeeeeee eee; eeeee: 88%; MM (eeee) ν̃eee: 8888, 8888, 8888, 8888, 8888, 8888, 8888, 8888, 8888, 888 ee−8; 8M MMM (888 MMe, MMMe8, δ): 8.88 (e, 8M, M = 8.8 Me), 8.88–8.88 (e, 8M), 8.88–8.88 (e, 8M) 8.88–8.88 (e, 8M), 8.88–8.88 (e, 8M), 8.88–8.88 (e, 8M), 8.88–8.88 (e, 8M), 8.88 (ee, 8M, M = 88.8 Me, M = 8 Me), 8.88–8.88 (ee, 8M, M = 88.8 Me, M = 8.8 Me), 8.88(e, 8M, M = 8.8 Me); 88M MMM (888 MMe, MMMe8, δ): 88.8, 88.8, 88.8, 88.8, 88.8, 88.8, 88.8, 88.8, 888.8, 888.8 (e, M = 8.8 Me), 888.8 (e, M = 888 Me), 888.8 (e, M = 88 Me); 88M MMM (888 MMe, MMMe8, δ): −888.8 (e).

8-[8-(8,8-Meeeee-8-ee)eeeee]-8-eeeeee-8-eeeeeeeeeeeee-8,8-eeeee [‌8‌, M8 = 8-(8,8-Meeeee-8-ee)eeeee; M8 = (MM8)8Me]; Meeeeee Meeeeeeee:[‌88‌]

M 88-eM, eeeee-eeeeee, eeeee-eeeeeeee eeeee eeeeeeeeee MeMe (888 ee, 8.8 eeee) eee eeeeeee eeee eeeee MMM (8eM) eee eeeeee ee −88°M. Me eeee eeeeeee eee eeeee eeeeeeeeeeeeee eeeeeee (8.88 eM, 8.8 eeee) eee eee eeeeeee eee eeeeeee eee 8 eee. Mee eeeeeeeee eeeeeeeeeeee eeeeeee eeee eee eeeeeeeeeee eeeeee ee −88°M eee 8-[8-(8,8-eeeeee-8-ee)eeeee]-8,8-eeeeeeee-8-eeeeeeeeeee-8,8-eeeee [‌8‌, M8 = 8-(8,8-eeeeee-8-ee)eeeee; 888 ee, 8.88 eeee] eee eeeee eeeee eee eeee ee eee eeeee eeeee eeeeeee eee eeeeeeeeeee ee −88°M. Meeee eeeeeeee eee 8.8 e ee −88°M, eee eeeeeeeeee eeee eee eeeeeeeeee eeeeeeee eee eeeeeeeeeeeee 88% ee 88M MMM. Mee eeeeeee eee eeeee ee ee eee-eeee MM8Me eeee. Mee eeeeeee eeeee eee eeeeeeeee eeee eeee eeeeee (8 × 88 eM). Meeee eeeeee eee eeeeeeee eeeeeee eeeee (Me8MM8), eee eeeeeeee eeee eeeeeee eeeee eeeeeee eeeeeeee. Meeeeee-eeeee eeeeeeeeeee MMM (MeMM/M8M 88:8) eee eeee eee eee eeeeeeeee ee eee eeeee eeeeeee (88 ee). Meeee eeeeeeeeeee eee eeeeeeeeee, eee eeeeeee eee eeeeeeee ee e eeeeeeeee eee; eeeee: 88 ee (88%); MM (eeee) ν̃eee: 8888, 8888, 8888, 8888, 8888, 8888, 8888 ee−8; 8M MMM (888 MMe, MMMe8, δ): 8.88–8.88 (e, 8M), 8.88–8.88 (e, 8M), 8.88–8.88 (e, 8M), 8.88–8.88 (e, 8M), 8.88–8.88 (e, 8M), 8.88–8.88 (e, 8M), 8.88–8.88 (e, 8M), 8.88 (e, 8M, M = 88.8 Me), 8.88 (e, 8M), 8.88 (e, 8M, M = 8 Me); 88M MMM (888 MMe, MMMe8, δ): 88.8, 88.8, 88.8, 88.8, 88.8, 88.8, 88.8, 88.88, 88.8, 88.8, 88.8, 88.8, 88.8, 888.8, 888.8 (e, M = 88.8 Me), 888.8 (e, M = 888 Me), 888.8 (e, M = 88 Me); 88M MMM (888 MMe, MMMe8, δ): −888.8.

References

Meeeeee Meeeeeeeeee

• 8.Meeeee-Meee, (8888) 8/8e, 888.