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 Carbonyl-Ene Reactions

DOI: 10.1055/sos-SD-213-00165

Kaposi, M.; Witt, J.; Cokoja, M.; Kühn, F. E.Science of Synthesis: C-1 Building Blocks in Organic Synthesis, (20142296.

The ene reaction is the “indirect substituting addition”[‌27‌] of a compound with a double bond (enophile) to an alkene possessing an allylic hydrogen (ene). If the enophile is a carbonyl compound, such as formaldehyde, the reaction is referred to as a “carbonyl-ene” reaction. The reaction involves allylic shift of one double bond, transfer of the allylic hydrogen to the carbonyl, and bonding between the two unsaturated termini.[‌28‌] It is mechanistically related to the Diels–Alder addition, but the activation energy for an ene reaction is higher due to the necessary cleavage of a C—H σ-bond.[‌29‌] Therefore it is induced either thermally or catalytically using a Lewis acid.

Mee eee ee eeeeeee Meeee eeeee, eee eeeeeee eeeeeeee eeeeeeeeeee, eeeee eeeeeeeeeee, ee eee(MM) eeeeeeee, eee eeeeee ee eeee eeeeeeeee, eeee ee eeeeee-eeeeeeeee eeeeeeeee ee eee eee (e.e., eeeeeeeeeeeeee) eee eee eeeeeeeeeeeee ee eeeeee eeeee ee eee eee ee eee eeeeee. Meeeeeeeeeeee eeeeeee eee ee eeee ee Meeee eeeee ee eeeeeee eee eeeeeeeee; eeeee eeeeee-eeeeeeeeee eeeeeeeee eeeeeeee eeee eeeeeeeee.[‌88‌] Meeeeee, eee eeeee eeeee ee eeeeeeeeeeeee eeeeeee eee eeeee ee e eeeeeeeeeee ee eeee ee e eeee eee eee, eeeeeeeee, eee ee eee eeeeeeee ee eeee eeeeeeeee eeeeeeee. Meee eeeeeee eee ee eeeeeee eeee eeee eeeeeeeeeeee eeeeeeeeeeeeeeee eeeeeeee ee eeee ee e eeeeeeee eeeeeee ee eeeeeeeeeeeeeee eeeeeeee, eeeeeeee eeee eeeeeeee eeee. Meeeeeeeeee, eeeeeeeeeeeeeeee eeeeeeee ee eeee ee eeeeeee eee eee eeeeeeee ee eeeeeeeeeeee eeee eee eeeee ee eeeeeee eee eeee eeeeeeee eeeeeee,[‌88‌] eeeeeee eeeee eeeeeeeeeee ee eee(MM) eeeeeeee eee eeee eeeeeeeee eeeeeeeee eeee 8,8-ee- ee eeeeeeeeeeeeee eeeeeee. Meeeee eeeeeeee eee eeeeee ee eeeeeeeeee eeee eeeee eeeeeeeeeeeeeeee eeeeeeee ee eee eeeeeeee eee eee eeeeeeeee ee eeeeeeeeeeee ee eeeeeeeeeee eeee eeeeeeeeeeee; eeeeeee eeeeeee eee eeeeeeeee eeee eee eee eeeeeee (Meeee 8).[‌88‌] Mee eeeeeeeeee ee 88 eeeeeeeee Meeee eeeee (eeeeeeeee MeMe8 eee Me8MeMe) eee eeeeeeeeeeee ee eeeeeeee-eee eeeeeeeee eeeeeee eeeeeeeeeeee eee eeeeeeee eeee eeeeeee eeeee eeeeeee eeeeeeeeee eeeeee (MMM) eeeeeeeeeeee. Mee eeeeeee eeee eeee eee eeeee eeeeeeeeee eeeeee ee eeeeee eeee eeeeeeee eeeeeeeeeee ee eeee (88.8 eeee · eee−8), eee eeeeeeeeeeeeeeee eeeeeeee eeee eeeeeee eee eeeeeeeeee eeeeee eeeeeeeeeeeee (eeee 88.8 eeee · eee−8 ee eee eeeeeee ee e Meeee eeee ee 88.8 eeee · eee−8).[‌88‌]

Meeee 8 Meeeeeee ee Meeeeee eee Meeeeeeeeeee eeee Meeeeeeeeeeeee Meeeeeee[‌88‌]

Meeeeeeee Me8MeMe (Meeee) Meeeeee(e) Meeee (%) Mee
8.8 88 + 8 [‌88‌]
8.8 88 + 8 [‌88‌]
8 88 [‌88‌]
8 88 [‌88‌]
8 88 [‌88‌]

Meeeeee eee eeeeeeee eeeeeee e eeeeeeee ee e eeeeeeeee eeeeeeeee eeeeeee ee eee eeeeeeee eeeeeeeeee. Mee eeeeeeeee eee eeee eeeeeeeeeeee eeee eeeee; Meeeee eee Mee eeeeeeeee eeee Meeee eeee eeeeeeeee eee eeeeeeeee ee eee eeeeeee eeeeeee eeeeee e eeeeeeeee eeeeeeeeee eeeeeeeee ee e eeeeee eeeeeeee eeeeeeeee, eee eeeeee eeeeeee e eeee eeeeeee eeeeeeee eeeeeeeee.[‌88‌]

Meeeeeeeeeee Meeeeeeee

Meeeeeee 88; Meeeeee Meeeeeeee:[‌88‌]

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

Mee Meeee eeee eeee eee eeeee eee eeeeeee ee e eeee ee eee eeeeeeee eee eeeeee ee MM8Me8 ee e eeeee-eeeee eeeee, eeeee eee eeeeee ee ee eee eeee, eeeee M8. Mee eee eeee eee eeeeeee eee eee eeee eee eeeeeee eeee eeeeeeeeee ee MM ee MMM. Meeeee eee eeeeeeeeeeee ee eeee eeeeeeee ee MeM8MM8 eeee (8 eM) eee Me8M (88 eM) ee eee eeeeeee. Mee eeeeeeeeeeee eeeeeee eee eeeeeeeee ee eeeeeeee eeeeeeee ee 88% MMe. Mee eeeeeee eeeee eee eeeeeeeee. Mee eeeeeee eeeee eee eeeeee eeee Me8M (8 ×). Mee eeeeeeee eeeeeee eeeeee eeee eeeee (MeMM8) eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee. Meeee eeee eeeeeeee ee eeeeeeeeee eeee MM8Me8.