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 Variation 1: Titanium-Promoted Cyclization of Diynes

DOI: 10.1055/sos-SD-046-00090

Gandon, V.; Thorimbert, S.; Malacria, M.Science of Synthesis, (200946210.

The titanium-mediated syntheses of E,E-exocyclic dienes from substituted diynes 134 may be easily performed in the presence of titanium(II) alkoxides or cyclopentadienyltitanium derivatives. These reactions allow the preparation of five-, six-, or seven-membered carbo- or heterocycles.[‌117‌,‌118‌] For example, the intermediate titanacyclopentadienes 135 can be trapped with aldehydes, and the adducts then hydrolyzed to give highly functionalized dienes 136 (Scheme 45).[‌119‌]

Meeeee 88 Meeeeeee-Meeeeeee Meeeeeeee Meeeeeee ee Meeeee, Meeeeeee ee Meeeeeeeeeeeeeeee[‌888‌]

Meeeeeeeeeee Meeeeeeee

(8M)-8-[(8M)-8-Meeeeeeeeeeeeeeeeeeeeeeeee]-8-eeeeee-8-(eeeeeeeeeeeeee)eeeee-8-ee [888, M8=Me; M8=(MM8)8Me; M=MM8]; MeeeeeeMeeeeeeee:[‌888‌]

8.88M eMeMeMe ee Me8M (8.888eM 8.888eeee) eee eeeee eeeeeeee ee e eeee ee 8-eeeeee-8-(eeeeeeeeeeeeee)eeee-8,8-eeeee (888, M8=Me; M=MM8; 88ee, 8.888eeee) eee Me(MeMe)8 (8.888eM, 8.888eeee) ee Me8M (8.8eM) eeeeeeeee ee 88°M eee eeeeeeeee eeeee eeeee. Meeee eeeeeeee eee 88eee, eee eeee eee eeeeee ee 88°M eeee 88eee eee eeee ee eeee eeeeeeeeeee eee 8e. Mee eeee eee eeee eeeeeeee ee 88°M, 8.88M [MeMe8(MeMe)8] ee Me8M (8.888eM, 8.888eeee) eee eeeee eee eee eeeeeee eee eeeeeee ee 88°M eee eeeeeee 88eee, eeeeee 8-eeeeeeeeeeeeee (8.888eM, 8.888eeee) eee eeeeeeeeee. Mee eeee eee eeeeeee ee eeee eeeeeee ee 8°M eee eee eeeeeee eeeeeeeee ee eeee eeeeeeeeeee. Mee eeeeeeee eee eeeeeeee ee eee eeeeeeee ee ee MeMMM8 eee eee eeeeeee eee eeeee (Me8MM8), eeeeeeeeeeee, eee eeeeeeeeeeeeeee (eeeeee eee) ee eeeeee e eeeeeeeee eee; eeeee: 88ee (88%).