Table 7. Synthesis of β-alkynyl ketones via sequential catalysis ^a .

^aReaction conditions: (i) 7 : 6 ratio = 1.5–2.0 : 1.0, 5 mol% Pd(OAc)₂/TDMPP, 1.0 M in PhMe at 23 °C for 14 or 24 h. (ii) 5 mol% Cu(OAc)₂·H₂O/17, (EtO)₂MeSiH (2 equiv.), 0.20 M in PhMe at 23 °C for 0.25–2 h, followed by quenching with TBAF (1.0 M in THF, 3.5 equiv.). Yields are of isolated products after chromatography. Enantiomeric excesses were determined by chiral HPLC analysis.

^bThe coupling was performed using a 2.0 : 1.0 ratio of 6i : 7l.

^cThe reduction was conducted at 0 °C, and the silyl enol ether was quenched using 1% HCl in MeOH instead of TBAF.