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.
3.6.11.1 Gold-Catalyzed Cycloisomerizations of Enynes

DOI: 10.1055/sos-SD-103-00001

López-Carrillo, V.; Echavarren, A. M.Science of Synthesis Knowledge Updates, (20112101.

Gold(I) salts and complexes are the most alkynophilic amongst the electrophilic metals that catalyze cyclization of 1,n-enynes.[‌1‌‌13‌] Gold(I) complexes are highly selective Lewis acids with a high affinity for π-bonds linked to relativistic effects, which reach a maximum with gold.[‌6‌,‌14‌‌16‌] In the reactions of 1,6-enynes 1, the alkyne group is selectively activated by a cationic gold species {[AuL]+} to form an alkyne–gold(I) complex, which reacts intramolecularly with the alkene by formal 5-exo-dig or 6-endo-dig cyclization to form intermediates 2 and 3, respectively (Scheme 1).[‌1‌] A number of alkyne–gold complexes have been characterized[‌17‌‌21‌] and studied in solution.[‌22‌‌25‌]

Meeeee 8 Meeeeee Meeeeeee Meeeeeee ee eee Meee(M)-Meeeeeeee Meeeeeeeeee ee 8,8-Meeeee

Meeeeeee eee eeee eeeeeeee ee eeeeeeeeeeee ee 8,e-eeeeee eeeeeeeee ee eeee(M) eee ee eeeeeeeee ee eee eeeeeeeee eeeeeeeeee ee eee eeeeee eeeeeeee ee eeee, eeeeeeeee ee eeee(M) eeee eee eeeeee eeeeeeee ee eee eeeee eee eeeeeeee eeeeee ee eeeeeeee ee eeeeeeeeeee eeee eee eeeeee–eeee eeeeeeeee.[‌88‌] Meeeee, eeee-eeeeeeeeeeeee eeeeeeeee ee eeee(M) eeee eeeeeee eee eeeee[‌88‌‌88‌] eee eeeee eeeeeeeeee eeee eeee eeeeeee ee eeeeeeee.[‌88‌,‌88‌,‌88‌,‌88‌] Mee eeeee-eeeee eeeeeeeee ee e eeeeeeee eeeeee–eeee(M) eeeeeee eee eeee eeee eeeeeeeeee.[‌88‌]

Meeeeeeee ee M–M eeeee eee ee eeeeeeeee ee eeee(M) ee eeee(MMM) eeeee ee eeeeeeeee. Meeeeee, eeee(MMM) eee ee eeeeeee ee eeee(M) ee eeeeee eeeeeeeeee eeeeeeeeee.[‌88‌] Mee eeee eeeeee eeee eeeeeeeee eee eeeeeeee eeeeeeeee [Me(M)(M)]M (M = eeeeee; M = eeeeeee ee eeeeeeeee eeeeeeee) eeeeeeeee ee eeee ee eeeeeeee eeeeeeeeeee eeee eeeeeeeee [MeMe(M)]. Meee, eee eeeeeeeeeee eeeeee(eeeeeeeeeeeeeeeeee)eeee(M) (ee eeeee eeeeeee eeeeeeeee eeeeeee) eeeeee eeee 8 eeeeeeeeee ee e eeeeee eeee eeee e eeeeeeeeeeeeeee eeeee ee eeeeeeee ee eeee eee eeeeeeee eeeeeeee {[Me(MMe8)(M)]M}.[‌88‌,‌88‌] Meeeeee eeeeeeee eeeeeeeee eee ee eeeeeeee ee eeee ee eeeeeeee ee eee Me–Me eeee ee eeeeee(eeeeeeeeeeeeeeeeee)eeee(M) eeee e eeeeee eeee.[‌88‌,‌88‌‌88‌] Meee eeeeeeeeeeee, e eeeeeeee eeeeeee {[Me(MMMe)(MMe8)]MeM8} eee eeee eeeeeeee ee e eeeeee eeeeeeeeeee eeeee, eeeee eeeeee eeee(M)-eeeeeeeee eeeeeeeee ee ee eeeeeeeee ee eee eeeeeee ee eeeeee eeeee.[‌88‌] M eeee–eee eeeeeee {[(Me8MMe)8M]MM8}[‌88‌,‌88‌] eee eeee eeee eeee ee e eeeeeeee ee eeeeeeeee ee eeeeee.[‌88‌]

Meee(M) eeeeeeeee 88 eeeeeee eeeee, eeeeeeee-eeeee eeeeeeeeee, eeeee eeee eeee eeeee ee ee eeeeeeeee eeeeeee eee eeeeeeeee-eeeeeeeee eeeeeeeee,[‌88‌,‌88‌] eeee ee eeeeee eeeeeeeee eeee eeeeeeeeee eeee eeeeee(M) eeeee (Meeeee 8).[‌88‌] Meee eeeeeeeeee ee eeeeeeeee eee eeeeeeee eeeeeeeee 888, eeeee eee eeeeee eeeeeeeeeee eeeeee eeee eee ee eeeeeee eeeee eeeeeeee eeeeeeeeee,[‌88‌,‌88‌] eee eee eeee eeeeeeee ee eeeeeeeee ee e eeeeeee ee eeeeeeeeeeeeeee.[‌88‌‌88‌] Meeeeee eeeeeeeee 88 eee 88 eeee e eeeeee eeeeeeeeeee eee(eeeeeeeeeeeeeeeeeeeeeee)eeeee eeeeee eeee eeee eeee eeeeeeee.[‌88‌] Meee eeeeeeeee eeee eeeeee eeeeeeee-eeeeeeee M-eeeeeeeeeeee eeeeeee eeeeeee[‌88‌‌88‌] eeee ee 8888 eee eeee eeee eeeeeeeeeeee.[‌88‌,‌88‌‌88‌] Meeeeeee eeeeeee 88 eee 88,[‌88‌] eee eeeeeee eeeeeeeee,[‌88‌,‌88‌] ee eee eeee ee eeeeeee eeeeeee 88 eee 88[‌88‌,‌88‌] eeeeeee eee 8,8-eeeeeeeeeeeeeeeee-8-eeeeeee (MMee) eee 8,8-eee(8,8-eeeeeeeeeeeeeeeee)eeeeeeee-8-eeeeeee (MMe) M-eeeeeeeeeeee eeeeeee eeeeeee eee eeeeee eeeeeeeee ee eeee eeeeeeeeeeee. M eeeeeeeeeee(M) eeeeeee [Me(MM)(MMe)] eee eeee ee eeee ee e eeeeeeeeeee eeee eee ee eeeeeeeee eeee Meøeeeee eeeee.[‌88‌,‌88‌] Meee eeeeeeee[‌88‌‌88‌] eee eeeee eeeeeee eeeeeeee[‌88‌,‌88‌‌88‌] eeee eeee eeee ee eeeeeeeee eeeeeeeee ee eeeeeeee eeeeeeeeeeeeeeee. Meee(M) eeeeeeeee eeee eeee eeeeeeee eeeeeeeee ee eeeeeeeeeeeeeee eeeeeee eee eee eeee eeeeeeeeeeeee eeeeeeeee.[‌88‌,‌88‌] Me eeeeeeeeee, eeeeeee eeeeeeeee eeeeeee 88/eeeeee(M) eeeeeeeeeeeeeeeeeeee[‌88‌] eee eee eeeeeeee eeeeeeee 88, eeeeeee eeee(8,8-ee-eeee-eeeeeeeeeee)eeeeeeeee, eee eeeeeee eee eeee eeeeeeee eeee(M) eeeeeeeee eee eee eeeeeeeeee ee eeeeeee.[‌88‌]

Meeeee 8 Meeeeeee Meee(M) Meeeeeeee Meee ee Meeeeeeee ee Meeeeeeeeeee

References