0 Hits

  • Previous / Next

You are using Science Of Synthesis as a Guest.
Please login or sign up for a free trial to access the full content. Variation 1: Hydrolysis of N-Arylhydrazones

DOI: 10.1055/sos-SD-025-00109

Plietker, B.Science of Synthesis, (200725156.

Owing to hyperconjugation effects, N-arylhydrazones are amongst the most stable hydrazones. Although they may be cleaved in the presence of strong Brønsted acids such as hydrochloric acid[‌35‌] or polyphosphoric acid,[‌36‌] addition of Lewis acids often proves beneficial. A variety of Lewis acid activated, Brønsted acid catalyzed hydrolysis processes have been developed (Table 3).[‌37‌‌41‌] In some cases, silica gel is added as a proton source. In other cases the Brønsted acid is formed in situ upon hydrolysis of the added Lewis acid.

Meeee 8 Meee-Meeeeeeee Meeeeeeeee ee M-Meeeeeeeeeeeee[‌88‌‌88‌]

M8 M8 Meeeeeeeee Meeee (%) Mee
(MM8)8Me Me MeMe88M8M, eeeeee eee, MMM, M8M, eeee, 88eee 88 [‌88‌]
8-MeMM8M8 Me MeMM88M8M, MMM, MeMM, M8M, eeee, 8e >88 [‌88‌]
8-M8MM8M8 Me MeM8Me, eeeeee eee, eeeeee, M8M, eeee, 88eee 88 [‌88‌]
8-M8MM8M8 Me MeMM88M8M, MMMe8, ee, 88eee 88 [‌88‌]
8-Mee 8-M8MM8M8 Me(MMM8)8, eeeeee eee, eeeeee, M8M, ee, 88eee 88 [‌88‌]

M eeee eeeeeeeee ee eee eeeeeee eeeeeeee ee eeeeeeee eeeee e eeeeeeeeeeeeee eeeeeeeee. Meeeeee eeeeeeeee eee eeee eeeeeeeeeeee eeeeeeee eeee eeee eeeeeeeee. Meøeeeee eeeee eeee ee eeeeeeeeeeee eeee ee eeeeee eeee eee eeeee ee eeeeeeee eee eeeeeee.[‌88‌] Meeee, e eeeeeeeeeee ee eeeeeeeeeeeeeeeeeeeeeeee eeee[‌88‌] ee eeeeeeeeeeeeeeeeee eeee[‌88‌] eee ee eeee ee eeeeeee eeee eeeeeeeeee ee M-eeeeeeeeeeeee 8 ee eeee eeeeeeee 88 (Meeeee 8).

Meeeee 8 Meeeeeeeee ee ee M-Meeeeeeeeeeee[‌88‌]

Meeee eeee eeeeeeeeee ee eee eeeee eeeeee eeeeeee eeeeeeeeeee ee eeeeeeeeeeee ee eee eeeeeeee eeeee, eee eeeeeeeeee eee eeeeeeee-eeee π-eeeeee eeeeeee ee eeeeeeeeeeeeee eeeeee eee eeeeeeeee eeeeeeeee eeeeeeeeeeee. Meeeeee eeeeeeeeeeee-,[‌88‌‌88‌] eeeeeeee-,[‌88‌‌88‌] ee eeeeeee-eeeee[‌88‌,‌88‌] eeeeeeeee eeeeee eee eeeeeeeeee ee eee eeeeeeeeee ee eeeeeeeeee (Meeee 8).[‌88‌‌88‌] Meeeeee, eeeeeeeeeeeee eee ee eeeeeeeeeee. Meeeeeeeeee, eeeeee eee eeeee eeeee eee eeeeee eeeeeeee eeee eeeee eeeeeeeeeeeeee eeeeeee ee eeeeeeee-eeeee eeeeeeeee eeeeee. Meeeeeeeeee eeeeeeeee eeeeeeeeeeee eeeeeeeee eeee eeee eeeeeeeee eeee eeeee eee e eeee eee eeeeeeeeeeee eeeeeeee eeeeeeeee ee eee eeeeeee eeeeeeee.[‌88‌‌88‌]

Meeee 8 Meeeeeeee Meeeeeeeeeee ee M-Meeeeeeeeeeeee[‌88‌‌88‌]

M8 M8 Meeeeeeeee Meeee (%) Mee
8-eeeeeee Me MeMe, Meeeeeeeee, M8, MM8Me8, ee, 88eee 88 [‌88‌]
8-MMM8M8 Me MMM, eeeeee eee, eeeeeeeee, 8eee >88 [‌88‌]
Me Me Me(MM8)8, M8MM8, MeMM, eeee, 88eee 88 [‌88‌]
8-M8MM8M8 Me eeeeeee-eeeeeeeee MeM(MMe)8, MM8Me8, M8M, ee, 8e 88 [‌88‌]
8,8-(M8M)8M8M8 8. M8, MeMMe, 88°M
8. MMM, MeMMe, 88°M ee ee
88 [‌88‌]

Meeeeeeeeeee Meeeeeeee

8M-Meeee-8-eeeeeeeeeeeeeeeeeee (88); Meeeeee Meeeeeeee:[‌88‌]

MMMMMMM: Meeeeeeeeeee ee e eeeeeeee eeeee eeeeeeeeee, e eeeeee eee, eeee, eee eeeeeeeeeee eeeee eeeeeeee, eee e eeee eeeeeeeeee.

Me e eeee ee eee eeeeeeeeeeeeeee 8 (888ee, 8.8eeee) ee eeeeeee (88eM) eee eeeee e 88% ee MMMM (8eM) eee eeeee MMe (8eM). Meeeeeee eee eeeeeeeee eee e eeeeeee 88eee ee ee. Mee eeee eee eeee eeeeee eeee eee eee eeeeeeeee eeee MM8Me8. Mee eeeeeeee eeeeeee eeeeee eeee eeeeee eeeeeee eeeee eeee M8M, eeeee (MeMe8), eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee ee <88°M. Mee eeeeeee eee eeeeeeee ee eeeeeeeeeeeeee (eeeee eeeeeee, eeee MMM) ee ee eeeeeeeeeee (88°M/8.88Meee). Mee eeeeeee eee eeeeeeee ee e eeeeee eeeee; eeeee: 888ee (88%).