Navigation

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
3.4.5.3.2 Variation 2: Conjugate Addition Reactions

DOI: 10.1055/sos-SD-003-00274

Heaney, H.; Christie, S.Science of Synthesis, (20043586.

Conjugate addition reactions to α,β-unsaturated carbonyl compounds with alkylcyanocuprates proceed in the expected manner. A comprehensive set of experiments aimed at determining the relative electron transfer ability of alkylcopper sources provides an interesting method of comparing the ability of different reagents for conjugate addition reactions.[‌1533‌] The drawback of some copper species is that they can reduce double bonds, as well as add in a conjugate fashion. By measuring the ratio of reduced to conjugate addition products, a rough scale can be formulated into which the various types of alkylcopper species can be ranked. For this section in particular, it is noteworthy that cyanocuprates are particularly effective at conjugate addition reactions, and it appears that the cyano ligand also suppresses the reduction of the α,β-unsaturated system. Gilman cuprates, which are discussed later (Section 3.4.7), produce more of the reduced compounds. The addition of cyanocuprates to chiral substrates can lead to diastereocontrol in forming the products. This can occur either at the center where the nucleophile adds, i.e. the 4-position, or where the putative enolate is quenched, the 3-position.

Meeeeee eeee eee eeeeee eeeeeeeeeeee eee eeee eeeeeeee eeeeee eeeeeeee ee eeeeeeeeeeeee ee α-eeeeeeeeeeeeeeeeeeeeeee eeee eeeeeeeeee eeeeeeeeeeee.[‌8888‌] Me eeeee ee Meeeee 888, eeeeeeee ee eeeeeeeeeeeeeeeeeee eeeeeeee ee eeeeeeee ee eeee eee eeeeeee. Meeeeee, ee eeeee ee eeeeeee eee eeeeeeeee ee eee eeeeeee eee eeee eee eeeeeeeee ee eee α-eeeeeeee, eeeeeeee ee eeeeeeeeeeeeeeeeeeeee eee eeeeeeeee. Meee eeee eeeeeeee e eeee eeeee ee eeeeeeeeeeeeee eeeeeeee.

Meeeee 888 Meeeeeeee Meeeeeee ee ee α-Meeeeeeee Meeeeee[‌8888‌]

Meeeeeee ee α,β-eeeeeeeeeee eeeeee eee eeee eeeee. Meeee e eeeeee(eeeeeeeeeeeeee)eeeee ee eeee eee eeeee, eeeeeeee eeee e eeeeee ee eeeeeeee eee eeee eeeee ee eeeeeee eeee eeee eeeeeeeeeeee, eee eeeeeeeeeee eeeeee ee eee 8-eeeeeeee (e.e., ee eeee 888, Meeeee 888).[‌8888‌]

Meeeee 888 Meeeeeeee Meeeeeee ee Meeeeeeeeeeeeeeeeee ee ee α,β-Meeeeeeeeee Meeee[‌8888‌]

Mee eeeeeeee ee eeeeeeee eeeeeeeee eeeeeeeee eee eeee eeeeee ee eeeeeeee eeeeeeee eeeeee eeee eeeeeee. Meee eeee ee eeeeeeee eeeee eee eeeee ee eeeeee eeeeeeeee, eee eee eeeeeee ee eeeeeee eeeeeeeee. M eeeeeeeeeeee eeeeeeeeee eeeeeee ee eee eeeeeeee ee e eeee-eeeee eeeee ee e 8,8-eeeeeee eeee eee eeeeeeee ee ee eeeeeee (Meeeee 888).[‌8888‌]

Meeeee 888 Meeeeeee Meeeeeeee Meeeeeee ee Me-eeee-eeeeeeeeeeeeeeeee[‌8888‌]

Me eeeeeeeee eeeeeeeeee, eee eeeeeeeeee ee eee eeeeeeee ee eeeeeeeeee ee eeee ee eeeeeee ee ee eeeeeeeeeee ee eeee eeee ee eeeeeeeeeeee. Meee eeee eeeeeeeeeeee, eee eeeeeee ee eee ee eeeeeeeeee eeeeeeeee eeeeeee eeeeee eee eee eeeeeeeee ee eeeeee eeeeeee ee8-eeeeeeeeee eeeeeee.[‌8888‌] Mee eeeee ee Meeeee 888 ee eeeeeeeee ee eee eeeeeeeee eeeeeeee eeeeeeeee: eee eeeee eeeeeeee ee 8,8-eeeeeee ee eeeeeee eee eeeee. Meeeeee, eeee ee eeee e Meeeeee eeeeeeee, eee e eeeeee eeeeeeee ee ee-eeee-eeeeeeeeeeeeeeeee eeeeeeee ee e 8,8-eeeeee ee eeeeeee eee eeeeee eeee eeeeeee eee(eeee-eeeee) eeeeeeeeeeee.

Meeeee 888 Meeeeeee Meeeeeeee Meeeeeee Meeeeeeee ee e Meeee[‌8888‌]

Meeeeeeee eee eeeeeeee eeeeeeeee ee eee eeeeeeeee eeeeeeee eeeee ee eeeeeeeee ee ee eeeeeee eeeee. Meee eee ee eeee ee eeeeeee MM eeee-eeeeeee eeeeeeeee ee eee eeeeeee eeeeeeeeeeeeeee eee eeeeeee ee eee eeeeeeee. Me eeeee ee Meeeee 888, eeeeeeee ee eeeeeeeeeeeeeeeeeee ee eee eeeeeee eeeee eeeeeeeee eeeeeeee eee Meeeeee eeeeeeee eeeeeee. Meeeeee, eee eeeeeeee ee eee eeeeeee eeeeeeee ee eeeee eeeeee eee eee eeeeeee eeeeeeeeeeee, eeeeeeee eeeeeeeee ee eee eeeeeeeeee eeee.[‌8888‌]

Meeeee 888 Meeeeeeee MeeeeeeeMeeeeee Meeeee Meeeeeeeeee[‌8888‌]

Meee eeee ee eeeeeeee eee eeee eeee eeeeeeee ee eeeeee Meeeeee eeeeeeee eeeeeeeee, eeeeeeee ee eeeeeee eee eeeeeee eeee e eeeeeee eeeeeeeee (Meeeee 888).[‌8888‌] Meeeeeee eeee eee eeeeeeeeeeeeee, eeeeeeee ee eeeeeeeeeeeeeeeeeeee eeeeee e Meeeeee eeeeeeee ee eeee eeeee. Mee eeeeeeeee eeeeeee eeee eeeeeeee eeee eeee eee eeeeeeeee, eeeeeeeee eee eeeeeeeeeee eeee. Mee eeeeeee ee e eeeeeee ee eeeeeeeeeeeee ee eee Meeeeee eeeeeeee eeeeee. Mee eeeeeeee eeeeeeee e eeeeee eeeeeeeeeee eeee eeeeeeee eeee eeeeeeee eeeeeeee, eee eeeeeeee eeee eeeeeeeeeee eeeee e eeeeeeeee eeeeee ee eee eeeeee eeeeee.

Meeeee 888 Meeeeeeee MeeeeeeeMeeeeee Meeeee Meeeeeeeeee[‌8888‌]

Me ee eeeeeeeeeee eeeeeeeee ee eee eeeeeee, eee eeeeeeeeeeee eee eeeee ee eeee eeee, eeeeeeeeeee, ee eeee eeeee ee eeeeeeee eeee eeeeee eeeeeeee. Mee eeeeeeeee eeeeeee eeee eeeeee ee e eeeeeeeee eeeeeeee eeeeee ee ee α,β-eeeeeeeeeee eeeeee ee eeeeeee e 8,8-eeeeeeee (Meeeee 888).[‌8888‌] Me eeeee, eeee eeee eeeee eeeeeeeeeeee eeeeeeee, eeee ee eeee-eeeeeeeeeeee, eee ee eeee ee eeee eeeeeeee.

Meeeee 888 Meeeeeeee ee Meeeeeeeeee Meeeeee ee Meeeeeeee Meeeeeee[‌8888‌]

Meeeeeeeeeee Meeeeeeee

(M)-M-(8-Meeeeeeeeeeeeeee)(eeeeeeeeeeeeee)eeeeeeeeeee (888); Meeeeee Meeeeeeee:[‌8888‌]

Mee eeeeeee Me8MeMeMeMM (8.8eeee) [eeee ee eee eeeeeeeeeeee eeeeee ee eeeeeeee ee MeMe (8 eeeee) ee MeMM] eee eeeeee ee MMM (8.8eM) ee 88°M. MM8MMe8 eee eeeee (8.888eM, 8.8eeee) eeeeeeee ee M-[(M,8M)-eeee-8-eeeeeeeee](eeeeeeeeeeeeee)eeeeeeeeeee (88ee, 8.8eeee) ee e eeee ee MMM (8eM). Mee eeeeeeee eee eeeeeee ee eeee eee eeeeeee eee 8e ee ee, eeee eeeeeeee ee eeeeeeee ee 8M MeMM, eee eeeeeeeee eeee Me8M. Mee eeeeeeee eeee eeeee (MeMM8) eee eeeeeeeeeeee ee eeeee ee eeee 888 ee e eeeeeeeee eee; eeeee: 88%.

References


Cookie-Einstellungen