Rhodium-catalyzed enantioselective alkynylative cyclization of allenyl aldehydes with terminal alkynes

Asymmetric addition of terminal alkynes to allenyl aldehydes took place in the presence of an acetylacetonate complex [Rh(acac)L∗] (L∗ = binap or segphos) as a catalyst to give indanol derivatives in high yields with high regio- and enantioselectivity. The acetylacetonate (acac) ligand on the rhodium is important for the selective formation of the indanol derivatives.

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2-(4-(Triphenylsilyl)but-1-en-3-yn-2-yl)indan-1-olC31H26OSiEe = 99%[α]D20=-45 (c 0.99, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2R)

6-Methoxy-2-(4-(triphenylsilyl)but-1-en-3-yn-2-yl)indan-1-olC32H28O2SiEe = 97%[α]D20=-14 (c 0.98, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2R)

5-Methoxy-2-(4-(triphenylsilyl)but-1-en-3-yn-2-yl)indan-1-olC32H28O2SiEe = 99%[α]D20=-39 (c 0.77, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2R)

6-Fluoro-2-(4-(triphenylsilyl)but-1-en-3-yn-2-yl)indan-1-olC31H25FOSiEe = 99%[α]D20=-35 (c 0.74, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2R)

2-Methyl-2-(4-(triphenylsilyl)but-1-en-3-yn-2-yl)indan-1-olC32H28OSiEe = 81%[α]D20=-32 (c 0.70, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2R)

2-(4-(Triisopropylsilyl)but-1-en-3-yn-2-yl)indan-1-olC22H32OSiEe = 98%[α]D20=-55 (c 0.80, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2R)

2-(5-(Methoxymethoxy)-5,5-diphenylpent-1-en-3-yn-2-yl)indan-1-olC28H26O3Ee = 95%[α]D20=-20 (c 0.94, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S, 2R)

2-(4-Phenylbut-1-en-3-yn-2-yl)indan-1-olC19H16OEe = 98%[α]D20=-33 (c 0.93, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2R)

2-(4-(4-Methoxyphenyl)but-1-en-3-yn-2-yl)indan-1-olC20H18O2Ee = 99%[α]D20=-58 (c 0.65, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2R)

2-(4-(Naphthalen-1-yl)but-1-en-3-yn-2-yl)indan-1-olC23H18OEe = 98%[α]D20=-65 (c 0.80, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2R)

2-(1-(1-(4-Chlorophenyl)-1,2,3-triazol-4-yl)vinyl)indan-1-yl acetateC21H18ClN3O2Ee = 99%[α]D20=-232 (c 0.35, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S,2R)