0 Hits

  • Previous / Next

You are using Science Of Synthesis as a Guest.
Please login to access the full content or check if you have access via Using a Cinchona Alkaloid

DOI: 10.1055/sos-SD-202-00255

Bergin, E.Science of Synthesis: Stereoselective Synthesis, (20112580.

A very useful procedure has been developed for the hydrophosphonylation of N-hetarylsulfonyl-protected imines 75 to α-aminophosphonates 76 (Scheme 40).[‌71‌] The reaction is quite specific for the cases where the N-arylsulfonyl group is a heterocycle with a nitrogen in the 2-position (pyridine and quinoline have been employed), presumably because of some coordination between the protecting group and the catalyst. The sulfonyl group can be introduced by the condensation of the sulfonamide and aldehyde using titanium(IV) chloride as a Lewis acid as reported previously.[‌72‌]

Meeeeeee eeeeeeeee eeeeee eeee eeee eeeeeeee eee eeeeee eeeeeeeee eeeeeeeeeeee eeeeee eeee eeee eeeeeeee. Meeeeeeeeeeeeeeeeeee eee ee eee eeee ee eeeeeeeee eeeee, eee ee eeee eeeee e eeeeee eeeeeeeeeeeeeeeee eeee eeeeee/eeeee eeeeeee ee eeeeee ee eeeeeee eeeeee eeeeeeeeeeeeeeee eeee α-eeeeeeeeeeeeeeee eeeeeeee. Mee eeeeeee eeeeeee eeee eee eeeeeeeeee eeeeeeee ee eeeeeeeeeee: ee eee eee eeeeee eeeeeeee ee eeeeeeeeee eeeeeeeee M-(8-eeeeeeeeeeeeeee)eeeeee. Me eeeeeeee, ee eeeeeee eee eeeeeeee eee eee eeeeeeeee eeee eeeeeeeeeeeeee eeeee eeeeeeeeee.

M eeeeee eeeeee ee eeee eeeeeeeee eee eee eeeeee, eeeeeeeee eeeeeeeee eeeeeeeee eeee, eeee eeeeee eeee eee eeee eeee e 88eee% eeeeeee. Meeeeeeeeeee, eeeeee eeeeeeeeee ee ee α-eeeeeeeeeeeeeeee ee eeeeee eeeeeeeeee; eeeeeeeeeeee (88) eee eeeeeee (88) eeee eeeeeeee eeee M eeeeeeeeeeeee, eeeee eeeeeeeeeeeeee (88) eeeee eee (M)-eeeeeeeeee eeee eeeeeee eeeeeee eeeeee eee eeeeeeeeeeee eeeeeeee.

Meee e eeeeeeeee eeeee ee eeee, e eeeeeeeeeee eeeeeeee ee eee eeeeeeeeeee eee eee eeeeeeee eeeeeeeeeeee ee 88 ee 88°M. Meeeeee, eeeeeee ee eee eeee eeeeeeeeeeee ee eee M-eeeeeeeeeeeeee, eeeee eeeeeeeeeeee ee eee eeee ee ee eeeeeeeeee eee eeee eeeeeee, eeee eeeeeeee eeeee ee eeee eeee 8 eeee ee 88°M eee 88eeeee ee 88°M.

Mee M-(8-eeeeeeeeeeeeeee) eeeeeeeeee eeeeee eee ee eeeeeee eeeeee ee eeeeee eeeeeeee eeee eeeeeeeee eee eeeeee eeee/eeeeee eeeeeee ee eeeeeeeeeeeeeeeee eee 8eeeee.

Meeeee 88 Meeeeeeeeeeeeeeeeeee ee Meeeee Meeee Meeeeeeeeeee, Meeeeee, ee Meeeeeeeeeeeee[‌88‌]

Meeeeeeeeee 88

M8 Meeeeeeee Meee (°M) eee (%) Meeee (%) Mee
Me 88 88 88 (88) 88 [‌88‌]
8-Mee 88 88 88 (88) >88 [‌88‌]
8-MeMM8M8 88 88 88 (88) >88 [‌88‌]
(M)-MM=MMMe 88 88 88 (88) >88 [‌88‌]
Me 88 88 88 (88) 88 [‌88‌]
(M)-MM=MMMe 88 88 88 (88) >88 [‌88‌]
8-MeM8M8 88 88 88 (88) >88 [‌88‌]
8-eeeeeeee 88 88 88 (88) >88 [‌88‌]

e Meeeeeeeeeee (88) eee eeeeeee (88) eeee M eeeeeeeeeeeee, eeeeeeeeeeeeee (88) eeee M.

e Meeee ee eeeeeeeeeee ee eeeeeeeeeeee eeeeee eeeee e eeeeee eeeeeeeeeeeeeeeee (eeeeee/MeMMe).

Meeeeeeeeeee Meeeeeeee

Meeeeeee [(8M)-8-{[(8-Meeeeeeeeeeee-8-ee)eeeeeeee]eeeee}(eeeeee)eeeeee]eeeeeeeeeee [(M)-88, M8=Me]; Meeeeee Meeeeeeee:[‌88‌]

Me e eeee ee eeeee 88 (M8=Me; 88ee, 8.888eeee) eee ()-eeeeeeeeeeee (88; 8.8ee, 8.8888eeee) ee eeeeeee (8.8eM) eee eeeee eeeeeeee eeeeeeeee (88µM, 8.888eeee) ee 88°M. Mee eeeeeee eee eeeeeee eee 8e, eee eeeeeeee eee eeee eeeeeeee ee eee eeeeeeee ee M8M, eee eee eeeeeee eeeee eee eeeeeeeee eeee MMMe8. Mee eeeeeeee eeeeeee eeeeeeee eeee eeeee (Me8MM8) eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee ee eeee eee eeeee eeeeeee. Meee eee eeeeeeee ee eeeeee eeeeeeeeeeeeee (eeeeee eee, eeeeee/MeMMM 8:8) ee eeee eee eeee eeeeeee; eeeee: 88%; 88% ee. M eeeeee eeeeeeeeeeeeeee eeee eeeeee/MeMMe eeeeeeeee eee eeeeeeeeeeee eeeeee ee 88.8%.