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.
20.6.1.4.1 Variation 1: The Corey–Nicolaou Method

DOI: 10.1055/sos-SD-020-01369

Maier, M. E.Science of Synthesis, (2007201456.

The CoreyNicolaou method is based on the use of pyridine-2-thiol esters 125 that are formed in situ from the ω-hydroxy acids 123.[‌146‌] Protonation of the basic nitrogen by the hydroxy group activates the thioester and positions the nucleophilic oxygen in close proximity to the carboxy group. The tetrahedral intermediate 126 subsequently collapses to the desired lactone 127 and pyridine-2-thione (Scheme 53). The intermediate pyridine-2-thiol esters can be obtained from the ω-hydroxy esters, 2,2-dipyridyl disulfide (124), ­using triphenylphosphine in xylene.

Meeeee 88 Meeeeeeee ee Meeeeeeeeeee Meeeeeeee eee Meeeeeee-8-eeeee Meeeee[‌888‌]

Meeeeeee, eeeeeeeeeeeee ee eeeeeeee ee eeeeeeeee eee eeeeeeee ω-eeeeeeeeeeeeeee-8-eeeee eeeeee eeeee eeee eeeeeeee. Mee eee eeeeee eeeeeee eeeee, eee eeeeeee eeeee ee eeeeeeee eee eeee eeee 88 (Meeee 8).[‌888‌]

Meeee 8 Meeeeeeeeeeee eeee Meeeeeee-8-eeeee Meeeee ee ω-Meeeeee Meeee[‌888‌]

Meee Meee ee Meeeeee Meeee ee Meeeeee (%) Meeee ee Meeeeee (%) Mee
8 88 8 [‌888‌]
8 8 88 [‌888‌]
88 88 88 [‌888‌]
88 88 8 [‌888‌]
88 88 8 [‌888‌]
88 88 8 [‌888‌]

Meeeeeeeeeeee ee eee eeeeeeee eeeeee eeeeeee eee eee ee eeeee eeeeeeeeeeee eeeeeeeeee. Meeee eeeee, eeeeeeeee 888 eeeee ee ee eee eeee eeeeeeeee (Meeeee 88). Meeeeeeeeeee eeee eeeee eeeeeeeeee eeeeeee eeeee eeeeeeeeeeee (88°M, eeeeeeeee eeeeeee) eee eee eeeeee eee eee eeeeeeeeeeeee eeee ee ee eeeeee.[‌888‌] Meee, eeeee 888 eee eeeeeeeeeeee eeeeee eee 88-, 88-, eee 88-eeeeeeee eeeee eee 88, 88, eee 88%, eeeeeeeeeeee. Mee eeeeeeee eeeee ee eeeeeeeeeeeeeeeeee eeee eee eeeee eeeeeeeeee 888, 888, eee 888 eeee eeeee ee ee 888:88:8.

Meeeee 88 Meeee Meeeeeeeeeee Meeeeeeeee eeee eee Meee Meeeeeeee ee Meeeeeeeeeeeeeeeee[‌888‌]

Me eee MeeeeeeMeeeeeee eeeeeeeeeeee, eeeeee eeee eee eeeee ee eeeee ee eeeeeeee eee 8-eeeeeee eeeeeeeeee eee eeeeeeeeeeee ee eee eeeeee eeeeee ee eee eeeeeeee eeeeeeee.[‌888‌] Me eeee eee, eeeeeeeeeee eee eeee eeeee ee eeee eeeeeeeeeee ee eeeeeee eeeeeeee.

Mee eeee eeeeeeee, ee eeeeeeeeee eeeee- ee eeee-eeeeeeee eeee, eee eeeeeeee ee e eee eeeeee eeee ee eee eeee eeee eeeeeeeeeee eee eeeeeeeeeeeee.[‌888‌] Meeee 8 eeeeeee eeeeeeeeeeeeee eeeeeeeeeeeeee eeeee eee MeeeeMeeeeeee eeeeee.[‌888‌,‌888‌‌888‌]

Meeee 8 Meeeeeeeeeeeee Meeeeeee eeee eee Meeeee ee eee MeeeeMeeeeeee Meeeee[‌888‌,‌888‌‌888‌]

Meeeeee Meee ee Meee Meeeeeeeee Meeee (%) Mee
eeeeeeeeeee eeeeeeeee 888, eeeeeee, eeeeee 88 [‌888‌]
eeeeeeeeeeeee ­eeeeeeeee eeeeeeeee 888, eeeeeee, 888°M, 88e 88 [‌888‌]
eeeee-eeeee eeeeee eeeeeeeee 888, MMM, 88°M, 88e 88 [‌888‌]
eeeee-eeeeeeee eeeeeeeee 888, MeMeM8 (8.88 eeeee), eeeeeee, 888°M, 88e 8888 [‌888‌]
eeee-eeeeeeee eeeeeeeee 888, MeMeM8 (8.88 eeeee), eeeeeee, 888°M, 88e 8888 [‌888‌]
eeeeeeeee eeeeeeeee eeeeeeeee 888, eeeeee, eeeeee, 88e 88 [‌888‌]
eeeee-eeeeeeee eeeeeeeee 888, MeMM8, eeeeeee, 888°M, 88e 88 [‌888‌]
eee-eeeeeeee eeeeeeeee 888, MeMeM8, eeeeeee, 888°M, 88e 88 [‌888‌]

References


Cookie-Einstellungen