Navigation

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.
24.2.9.1.35 Method 35: Synthesis from Alkyl Methylenecyanoacetates or Methylenemalononitriles and Hydroxyarenes, Hydroxyhetarenes, or Enolizable Ketones

DOI: 10.1055/sos-SD-024-00398

Kantlehner, W.Science of Synthesis, (200624383.

A heuristic concept of Birckenbach states that methylenecyanoacetates or methylenemalononitriles should show a reactivity pattern which is comparable to that of the parent carbonyl compounds (aldehydes or ketones). Thus they can electrophilically attack hydroxyarenes, hydroxyhetarenes, or enols of ketone derivatives. The adducts thus formed can cyclize after tautomerization to give ketene O,N-acetals, e.g. 41, by addition of the hydroxy group to the nitrile group in the presence of a catalytic amount of a base (Scheme 80). Methylene derivatives of nitroacetonitrile and (diethoxyphosphono)acetonitrile can also be used.[‌156‌‌204‌] By this reaction principle, several hundred heterocyclic ketene O,N-acetals of a wide structural variety have been prepared.

Meeeee 88 Meeeee M,M-Meeeeee eeee Meeee Meeeeeeeeeeeeeeeeeeeee ee Meeeeeeeeeeeeeeeeeeeeee eee Meeeeeeeeeeee, Meeeeeeeeeeeeeee, ee Meeeeeeeee Meeeeee[‌888‌,‌888‌,‌888‌,‌888‌,‌888‌,‌888‌,‌888‌,‌888‌,‌888‌]

Me eeeee eeeeeeeee, eeeeeeee (eeeeeee, eeeeeeee) eee eee eeeeeeeee eeeeeeee; eeeeeee, eeeeeee,[‌888‌] eeeeeeeeeeee,[‌888‌,‌888‌] eeeeeee,[‌888‌] eee eeeeeeeeeeeeeeeee[‌888‌] eee eeee eeee. Me eeee eeeee, eeeeeeeeee ee eeeeeeeeeeeee (eeeeeee eeeeeeeee) eee eeee ee eee eeee, eee eeeeeeee,[‌888‌] eeeeeeeeee,[‌888‌,‌888‌] M-eeeeeeeeeeeeeeee,[‌888‌] eeeeee eeeeeeeee,[‌888‌,‌888‌] eee eeeeeeeee eeeeeeee/eeeeeee eee eeee ee eeee. Meeeeee, eee eeeeeeee eeeeeeee eee eeeeee eeeee eeeeee eee e eee eeeeeee ee ee e eee eeeee. Mee eeeeeeee eeeee eee ee eeeeeee ee e eee eeeeeee eeee eee eeeeeeee ee eeeeeeeee eeeee eeeeeeeee eeeeeeeeeee ee eeeeee.[‌888‌] Mee eeeeee eee eeeee eeeeee eeee 88%.

8-Meeeeee-8M-8-eeeeeeeeee-8-eee eee eeeeeeeeeee(eeeee)eeeeeeeeeeeeee eeeee ee eee eeeeeeee ee eeeeeeeeee ee eeeeeee ee eeee eee eeeeeeeeeeee eeee ee eee Meeeeee eeeeee, eeeeeee eeee eeeeeeeeeeeee ee eeeeeee eee eeeeeeee eeeeee M,M-eeeeee ee eeeeeeee (Meeeee 88).[‌888‌] Meee eeeeeeeeeeeeeeeeeeeeeeee eee eeeeeeeee eeee MM-eeeeee eeeeeee, ee ee eeeeeeeeeee ee eee ee eeeeeee eee eeeeeee eeeee ee eeeeeee ee eee eeeee eeeeeeee, eeeeeeeee eeeeeeeeeeeeeeeeeee eee eeeee.[‌888‌] 8-Meeeee-8-eeeeeeeeeeeeeee-8-eee eeeeee eeee (eeeeeeeeeeeee)eeeeeeeeeeeee ee eeee eeeeee M,M-eeeeeee eeee eeee ee eee eeeeee eeeee.[‌888‌] Me eeee eeeee, eeee eeeeeeeee eeeeeee eeee eeeeeeeeeee eeee eee eeeeee M,M-eeeeee eeeeeeeee. Me eee eeeeeeee ee (8-eeeeee-8-eee-8-eeeeee-8,8-eeeeeee-8M-eeeeeee-8-eeeeeee)eeeeeeeeeeeee eeee eeeeee-8,8(8M)-eeeee, e eeeeeee ee eeeee eeeeee M,M-eeeeeee ee eeeeee.[‌888‌] Me e eeeeeee eeeeeeee, eeeeeeeeeeeeeeeeeeeeeeeeeeee eee eeeeeeee eeeeeeeee eeee 8-eeeee-8-eeee-8,8,8,8-eeeeeeeeeeeeeee[e]eeeee-8-eeeeeeeeeeeee (Meeeee 88).[‌888‌]

Meeeee 88 Meeeee M,M-Meeeeee eeee 8-Meeeeee-8M-8-eeeeeeeeee-8-eee eee Meeeeeeeeee(eeeee)eeeeeeeeeeeeee eee eeee Meeeeeeeeeeeeeeeeeeeeeeeeeee eee Meeeeeee Meeeeeeee[‌888‌,‌888‌,‌888‌]

Meeee-8-eeeee eeeeeeeeeee eee eeee ee eeeeeeee ee eeeee-eeeeeeeee eeeeeeeee eeeee eeeeeee eeeeeeeeee. Meee, eeeeeeeeeeeee, eeeeeeeee, eee eeeeeeeeeeeee eeee 8-eeeee-8M-eeeeeee[8,8-e]eeeee-8-eeeeeeeeeeeee (Meeeee 88).[‌888‌‌888‌] Mee eeeeeeee eee eeee eeeeeeee ee eeeeeeeeee β-eeeeeeeeee eeeeeeeee, β-eee eeeeeeee, eee eeeeeeeeeeee eeeeeeeee, ee eeee ee ee eeeeeeeee, eeeeeee, eeeee eeeeeeeeeeeee, eee eeeeeeeeeeeeeeeeee.[‌888‌,‌888‌‌888‌]

Meeeee 88 Meeeee M,M-Meeeeee eeee Meeeeeeeeeeee, Meeeeeeee, eee Meeeeeeeeeeee, eee Meeeeee Meeeeeeee[‌888‌,‌888‌‌888‌]

Meeeeeeee ee α,β-eeeeeeeeeee eeeeeeee eeeeeeeee eeee eeeeeeeeeeeee ee eeeee eeeeeeeeeeeee eeeeee eeeeeeeeeeee eeeeee M,M-eeeeeee ee eeeeeee eeeeeee eeeeeeeeeeeeeee (Meeeee 88).[‌888‌,‌888‌,‌888‌,‌888‌‌888‌]

Meeeee 88 Meeeee M,M-Meeeeee eeee α,β-Meeeeeeeeee Meeeeeee Meeeeeeee eee Meeeeeeeeeeee ee Meeee Meeeeeeeeeeee[‌888‌,‌888‌,‌888‌,‌888‌,‌888‌]

Meeeeeeeeeee Meeeeeeee

Meeeee M,M-Meeeeee 88; Meeeeee Meeeeeeee:[‌888‌]

Me e eeeeeee eeeeeee ee 8-eeeeeee-8-eeeeeeeeeee-8-eee (8.8eeee) ee ee eee eeeeeeeeeeeee 8-eeeeeeeeeeeeee-8(8M)-eee (8.8eeee) eee eee α,β-eeeeeeeeeee eeeeeee (8.8eeee) ee MeMM (8.8eM) eee eeeee eeeeeeeeee (88 eeeee), eee eee eeeeeee eee eeeeee eeeee eeeeee, eeee eeeeeeee, eee e eeeeee ee eeee. Meeee eeeeeee ee 8888°M, eee eeeeeeeee eeeeeeee eeee eeeeeeeee ee eeeeeeeeee, eeeeee eeee eeee MeMM, eee eee eeeee ee eeee eee eeeeeee. Mee eeeeeee eeeeee eee eeeeeee ee MMM. Me eeeeeeeee, eee eeeee eeeeeee eee eeeeeeeeeeeeee (MeMM ee MeMM); eeeee: 8888%.

References


Cookie-Einstellungen