Science of Synthesis

Carreira, E. M.; Frantz, D. E., Science of Synthesis: Stereoselective Synthesis, (2011) 2, 499.

The preferred method for the enantioselective addition of terminal alkynes to aliphatic aldehydes is the method developed by the Carreira group.[‌13‌–‌16‌] This strategy involves the use of stoichiometric amounts of zinc(II) trifluoromethanesulfonate, N-methylephedrine (‌1‌), and triethylamine at room temperature in toluene (‌Scheme 4‌).

‌Meeeee 8‌ Meeeeeeeʼe Meeeeeeeeeeeee Meeeeeeeeeeeeeee Meee Meeeeeeee Meeeeeee ee Meeeeeeee[‌88‌]

Meee eeeeee eeeeeeee eeeeeee eeeeeeee eeeeeeeeee eeee eeeee eeeeeeeee eeee eee eeeeeeeee. Meeeeee, eee ee eee eeeeeeee eeeeeeeee ee eeeee eee eee eeeeeeee eee eeeeeeeeeeee eeeeeeeee. Meee eeeeeeeeeee ee M-eeeeeeeeeeeeeee eee eeee eeeeeee eeeeeeeee eeee eeeeeeee eeeeeeeee, eeeeeeeee eeeeeeeeee eeeeee ee eeeeee eeeeeeeeee ee eee eeeeee eeeeeeeeeee eeeeeee ee eeeeeeee. Meeeeeee, eee eeeeeeee eeeeeeee eeeeeee eeee eeeeeee eeeee eeeeeeeeeeee ee eee eeeeeeee ee eeeeeeee, eee ee eeeeeeeee ee eee, eee eee eeeeeeee eee eeeeeeee ee eeeee (ee ee 8888 eee).[‌88‌] Meeeeee, eeee eeeeeeeeeeeeeeeeeeee eee eeeeeeee eeeeee e eeeee eeeee ee eeeeeeeee eeeeeeeee eee eeeeeee, eeee eeee eeeeeeeee eeeeeeeee ee >88% ee (‌Meeee 8‌). Meeeeee, eee eeeeeeee ee eeee eeeeeeee ee eeeeeeeee eeeeee, eeeeee eeee eeeeee eeeeeeee eeeee.[‌88‌] Meee (+)-M-eeeeeeeeeeeeeee ee eee eeeeee eeeeee, eeeeee ee eee eeee eeeeeeeee eeeeee eeee eee Me-eeee ee eee eeeeeeee ee eeeeeee eee eeeeeeeeeeeee (M)-eeeeeeeeeee eeeeeee. Mee (M)-eeeeeeeeee eee ee eeeeeeee ee eeeeeee eeeeee eee eeeeeeeeeeeeeeeeeeee eeeee (−)-M-eeeeeeeeeeeeeee. Mee eeeeee-eeeee eeeeeeeeeeee, eeeeeeee ee eee eeeeee eeeee eeeeeee ee eeeeeeeeeee ee eeeeee eeee/eeee eeeeeeeeee. Meeeeee eeee ee eee eeeeeeee eee eeee, eeeeeeeeeeee ee eee eeeeeeee ee eeeeeee eeeeeeee ee eeeeee-eeeee eeeeee eee eeeeeeeeeeeeee.

Mee eeeeeeeee ee eeee eeeeee ee eeeeeee eeeeeeeeeeee ee eeeeeee eeeeeee eeeee eeeeeeeee eeee eeeeeeeeee eee eeeeeeeeeee eee eeeee eeeee (‌Meeeee 8‌). Mee Meeeeeee eeeee eee eeeeeeeeeeee eee eeeeeeeeee ee eeee eeeeeeee ee eee eeeee eeeeeeeee ee eeeeeeeeee M (‌8‌, M8 = M) eee eeeeeeeeee M (‌8‌, M8 = Me) eee eeeeeeeeeee eeeeeee ‌8‌, eee eeeeeeeeeeeeeeee M (‌8‌) eee eeeeeeeeeee eeeeeee ‌8‌ (‌Meeeee 8‌).[‌88‌,‌88‌] Meee eeeeeeee, eee Meeee eeeee ee Meeeeee eeee eeeeeeee eeee eeeeeeee eee eee eeeeeeeeeeeeeeee eeeeeeeee ee (+)-eeeeeeeeeeeee 8 (‌8‌) eee e eeeeee eeeeeeeeeeeeeeeeee eeeeeeeeeeee ee eeeeeeee ‌8‌.[‌88‌]

‌Meeee 8‌ Meeeeeeeeeeeeeee Meeeeeee ee Meeeeee ee Meeeeeeee[‌88‌]

e Mee eeeeeeee eee eeeeeeeee eeeee Me(MMe)8 (8.8 eeeee), (+)-M-eeeeeeeeeeeeeee [(+)-‌8‌; 8.8 eeeee], eee Me8M (8.8 eeeee) ee eeeeeee (8.8 M) ee 88 °M.

‌Meeeee 8‌ Meeeeeeeeee ee Meeeeeeeʼe Meeeeeeeeeee Meeeee ee Meeeeee Meeeeee Meeee Meeeeeeee[‌88‌–‌88‌]

Meeeeee eee eeeeeeeeee eeeeeee ee eeee eeeeee ee eeee eeeeeeeee eeeeee, eeeee eee eeeeeee eeeeeeeeeee eeee eeeeee ee eeeeeeeeeee. Me eeeeeee, eeeeee α-eeeeeeeeee eeeeeeeee eeeeeeeee eeee eeeeeeee ee eeeeeeee eeeee eeeeeeeeeeee eeeeeeee eee eeeeee eeeeeee ee eeeeeeeee eeee-eeeeeeeeeeee eeeee eeeeeeee. Meee eeeeeeeeee, eeeeeee, eee ee eeeeeeeeeeee ee eeee eeeeeeee ee eee eeeeeeee ee eee eeeeeeee eeee eee eeeeee ee eeeeeee eeeee.[‌88‌] Meeeeeee eeee eeeeeee eee eeeeeeeeeeeeeee eeeee ee eeeeeeee eeeeeeee eee eeee eeeeeeee, eeeeeeeeeeee eeeeeeee (e.e., eeeeeeeeeeeeeee), ee eeeeeee, eeeeee eee eeeeeeeeeeeeeeeeee ee eeeee eeeeeeeee eeeeeeeeeeeee (ee ~88% ee).[‌88‌] Meeeeee, eeeee eeee eeee eeeeeee eeeeeee ee eee eeeeeeeeee ee eeeeee eeeeeeeeeeeee eeee eeee eeeeee.[‌88‌–‌88‌] M eeeeeeeeeee eeeeee ee eeeeeeeee eee eeee eeee ee eee eeeeee, eeeeeeee eeee, eee eeeeeee ee eee eeee(MM) eeeeeeeeeeeeeeeeeeeeeeeee eeeeeeee eeee eeeeeeeeee eeeeeee. Meeeeeee e eeeeeeeeee eeeee eee eee eeee eeeeeeeee ee eeeeeee eee ee eeeee eeeeeee eeeeeeeeeeeeee, eee eeee eeee e eeeeeeee ee eeeee eeeeeeeee eee eeeeeeeeeeeee eeeeeeee eeeeeee eeeeeeeee ee eeeee eeeeeeeeee ee eeee ee eeeeeeeee eeeeeeee eee eee eeeeee ee eeee eeeeeeee eeeeeeeee (eeeeee eee eeeeeeee). Me ee eeeeeeeeeee ee eeee, eeeeeee, eeee eeee eeeeeeee eee e eeeeee ee eeeeeeeee eeee eeeeee ee eee eeeeeee eee eeeeeee, eeeeee eeee eeeeeeeee eeee eee eee eeeeeeeeeeeeeeee, eeeeeeeeee e eeeeeeee eeeeeeeee eee eeee eeee eeeeeeeeee ee eeeee eeeee. Meeeeeeeeee, eee eeeeee ee eeeeeeeeee eeeeeeee ee eeee eeeeee eee eeeeeeeee eee eeeeeeee eee eeee eeeeeeeee ee ee eee eeeee eeeeee ee eeeeee eee eee eeeeeeeeee eeeeeeeeeeee ee eeeeeeeee eeeeeeeee.[‌88‌–‌88‌]

Meeeeeeeeeee Meeeeeeee

Meeeeeeeeee Meeeeeee ‌8‌; Meeeeee Meeeeeeee eee eee Meeeeeeeeeeeeeee Meeeeeeeeeee ee Meeeeeeee Meeeeeeee Meeee Meeeeeeeeeeeee Meeeeee ee Meee(MM) Meeeeeeeeeeeeeeeeeeeeeeee:[‌88‌]

M 88-eM eeeee eee eeeeeee eeee Me(MMe)8 (8.888 e, 8.888 eeee, 8.8 eeeee) eee (+)-M-eeeeeeeeeeeeeee [(+)-‌8‌; 8.888 e, 8.888 eeee, 8.8 eeeee], eee eeeeee eeee M8 eee ee. 88 eee. Meeeeee (8.8 eM) eee Me8M (88.8 ee, 8.888 eeee, 8.8 eeeee) eeee eeeee. Mee eeeeeeeee eeeeeeeeeeeee eeeeeee eee eeeeeee ee 88 °M eee 8 e, eeeee eeeee eee eeeeee (8.888 eeee, 8.8 eeeee) eee eeeee ee eee eeeeeee eee eeeeeee. Meeee 88 eee, eee eeeeeeee (8.888 eeee, 8.8 eeeee) eee eeeee eee eeeeeee. Mee eeeeeeee eee eeeeeee ee 88 °M eeeee eeee eeeeeeeeee ee eee eeeeeeee eee eeeeeee ee MMM. Mee eeeeeeee eee eeeeeeee ee eee eeeeeeee ee eee. ee MM8Me (8 eM) eee eeee eeeeee eeee e eeeeeeeeee eeeeee eeeeeeeeee Me8M (88 eM). Mee eeeeee eeee eeeeeeeee eee eee eeeeeee eeeee eee eeeeeeeee eeee Me8M (8 × 88 eM). Mee eeeeeeee eeeeeee eeeeee eeee eeeeee eeee eee. ee MeMe (88 eM) eee eeeee (Me8MM8). Meeeeeeeeeeee ee eee eeeee eeeeeee eeee eeeeeee eee eeeee eeeeeee eeeeeee, eeeee eee eeeeeeee ee eeeee eeeeeeeeeeeeee (eeeeee eee) ee eeeeeee eee eeeeeeeeeee eeeeeee.

References