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.
3.8.3.1 Stoichiometric Nazarov Cyclizations

DOI: 10.1055/sos-SD-203-00232

Gaspar, B.; Trauner, D.Science of Synthesis: Stereoselective Synthesis, (20113386.

The introduction of a silicon directing group can control the regioselective formation of the less substituted double bond in the cyclopentenone products.[‌17‌] For example, the vinylogous acylsilanes 18 undergo an iron(III) chloride mediated cyclization to afford the cyclopentenones 19 in moderate to excellent yield, favoring the cis-fusion in the bicyclic system (Scheme 6).[‌18‌] Various saturated and unsaturated chains, in addition to heteroatoms, are well tolerated in the reaction.

Meeeee 8 Meeeeee-Meeeeeee Meeeeee Meeeeeeeeee[‌88‌]

Meeeeeeeeee 8

M8,M8 M8 Meee (°M) Meee (e) Meeee (%) Mee
(MM8)8 MM8MM=MM8 88 8 88 [‌88‌]
(MM8)8 M 8 8 88 [‌88‌]
(MM8)8 M 88 8.8 88e [‌88‌]
(MM8)8MMe8MM8 M 8 8 88 [‌88‌]
MM=MMMMe8MM8 M 88 8 88 [‌88‌]
(MM8)8MM(MMe) M 8 8 88 [‌88‌]
(MM8)8M M 88 8 88 [‌88‌]
(MM8)8M(MM8Me) M 88 88 88e [‌88‌]
(MM8)8 M 8 8 88e [‌88‌]

e 8,8-Meeeeeeeeeeeee eee eeee ee eee eeeeeee.

e Meeee eeee eee MeMe8, ee 8,8-eeeeeeeeeeeeee.

e Meeeeee eeeeeeee ee e eeeeeeeeeeeeee eeeeeee; (eee/eeeee) 88:88.

Meeeeeeeee eeeeeeee ee eeee eeeeeeee eeee eeeeeee ee eee eeeeeeeeeeee ee eeeeee eeeeeeeeeee ee eeeeeee eeeeeeeeeeeeeeee eeeeeeee eeeeeeeeeeeeeee.[‌88‌,‌88‌] Mee eeeeeee, eeeeeeeee eee eeeeeeee 88 eeee eee eeeeeeeeeeeeee 88 eeeeeeee eee eeeeeeeeeeee eee-eeeeeee eeeeeeee, eeeee eeeeeeeee ee eeee-eeeeeeeee Meeeeee eeeeeeeeeee eeee eeeeeeeeeee eeee ee eee eeeeeee-eeeee eeeeee eeeeeeeee ee eeeeee eee eeeeeeeeeeeeeee 88 eeee eeee eeeeeeeeeeee eeeeee (Meeeee 8). Meeeeeeeeeeee, eee eeeeeee 88 eeee eee eeeeee-eeeeeeeeeee eeeeee 88 (M8=Me) eeeeeee eeeeeeeeee ee eee eeeeeeeeeeeeeeeee eeee eeeeee M-eeeeee, eeeeeee eee eeee-eeeee-eeeeeeeeeee eeeeeeeeee 88 (M8=e-Me) eeeeeeee eee eeeeeee eeeeeee eeee M-eeeeeeee.

Meeeee 8 Meeeeee-Meeee Meeeeeeee Meeeee Meeeeeeee ee e Meeeeee Meeeeeeeeee[‌88‌,‌88‌]

Meeeeeeeeee 8

M8 M8 M8 ee (%) Meeeee Meeee (%) Mee
M (MM8)8MM=MM8 eMe 88 88 [‌88‌]
M Me e-Me 88 88 [‌88‌]
M Me Me 88 88 [‌88‌]
M Me Me 88 88 [‌88‌]
Me Me Me 88 M 88 [‌88‌]
Me Me Me 88 M 88 [‌88‌]
e-Me Me Me 88 M 88 [‌88‌]
e-Me Me Me 88 M 88 [‌88‌]
e-Me Me Me 88 M 88 [‌88‌]

Meeeeeeeeeee Meeeeeeee

(M)-8-Mee-8-eeee-8-eeeeeee-8-eeeeeeeee-8-eeeeeeeeeeeeeeeeee-8-eeeee [88, M8=M; M8=(MM8)8MM=MM8; M8=eMe]; Meeeeee Meeeeeeee:[‌88‌]

Me e eeee ee eeeeee 88 (M8=M; 8.888e, 8.888eeee) ee MMM (88eM) ee 88°M eee eeeee 8.88M MeMe ee eeeeeee (8.88eM, 8.88eeee). Meeee 88eee, e eeee ee eeeee 88 [M8=(MM8)8MM=MM8; M8=eMe; 888ee, 8.88eeee] ee MMM (88eM) ee 88°M eee eeeee eee e eeeeeee. Mee eeeeeee eee eeeeee eeee 88 ee 88°M eeee 8e, eeeeee ee 88°M, eee eeeeeeee ee eeeee eeeeeeee, eeeeeee e eeeee-eeee eeeeeee, ee MMe ee MMMM/MMM (eeeeeeeee ee eeeeeeee ee 8.8eM ee MeMe ee e eeee ee 88eM ee MMMM eee 88eM ee MMM) ee 88°M. Mee eeeee eee eeeeeee eeee eee eeeeeee eeee, eee eee eeeeeee eee eeeeee ee ee, eee eeeeeee eeee eee. MeMMM8, eM8 eeeeee, eeeee, eee MeMMe. Mee eeeeeee eeeee eee eeeeeeeee eeee MeMMe (8×), eee eee eeeeeeee eeeeeee eeeeeeee eeee eeeeee eeee eeeee (8×) eee eeeee (MeMM8). Meeeeeeeeeee ee eeeee eeeeee eeeeeeeeeeeeee (eeeeee eee, MeMMe/eeeeeee 8:88 ee 8:8) eeee eeeeeeeeeeeeee 88 [M8=M; M8=(MM8)8MM=MM8; M8=eMe] ee e eeeeeeeee eee; eeeee: 888ee (88%); 88% ee.

References


Cookie-Einstellungen