. Author manuscript; available in PMC: 2012 Apr 1.

Published in final edited form as: J Org Chem. 2011 Mar 4;76(7):2350–2354. doi: 10.1021/jo200068q

Table 1.

Enhanced levels of anti-diastereo- and enantioselectivity in alcohol mediated carbonyl crotylations using the chromatographically isolated single component iridium catalyst (S)-I.^a

In Situ Method (ref. ^2c) [Ir(cod)Cl]₂ (2.5 mol%) (S)-SEGPHOS (5 mol%) 4-CN-3-NO₂BzOH (10 mol%) Cs₂CO₃ (20 mol%) THF (2.0 M), 90 °C, 48 hrs α-Methyl Allyl Acetate (200 mol%) For Aldehyde Substrates isopropanol (200 mol%)
	2a,3a: R = p-Br-Ph 2d,3d: R = 6-Br-2-Pyr 2g,3g: R = (CH₂)₂Ph	2b,3b: R = p-MeO-Ph 2e,3e: R = 3-Indolyl 2h,3h: R = (CH₂)₂NHBoc	2c,3c: R = p-(CO₂Me)-Ph 2f,3f: R = HC=CHPh 2i,3i: R = (CH₂)₂OPMB
Oxidation Level
Alcohol Aldehyde	Preformed (S)-I 78% Yield 4a, 16:1 dr, 97% ee 82% Yield 4a, 17:1 dr, 98% ee	Preformed (S)-I 91% Yield 4b, 10:1 dr, 95% ee 89% Yield 4b, 12:1 dr, 98% ee)	Preformed (S)-I 78% Yield 4c, 11:1 dr, 98% ee 81% Yield 4c, 13:1 dr, 98% ee
Alcohol Aldehyde	In Situ (S)-I 73% Yield 4a, 8:1 dr, 95% ee 78% Yield 4a, 11:1 dr, 97% ee	In Situ (S)-I 67% Yield 4b, 5:1 dr, 90% ee 75% Yield 4b, 7:1 dr, 97% ee	In Situ (S)-I 70% Yield 4c, 7:1 dr, 95% ee 80% Yield 4c, 11:1 dr, 96% ee

Alcohol Aldehyde	Preformed (S)-I 50% Yield 4d, 14:1 dr, 98% ee 75% Yield 4d, >20:1 dr, 97% ee	Preformed (S)-I 75% Yield 4e, 7:1 dr, 98% ee 74% Yield 4e, 10:1 dr, 98% ee	Preformed (S)-I^b 72% Yield 4f, 10:1 dr, 93% ee 77% Yield 4f, 10:1 dr, 98% ee
Alcohol Aldehyde	In Situ (S)-I no product observed	In Situ (S)-I 73% Yield 4e, 5:1 dr, 95% ee 78% Yield 4e, 6:1 dr, 97% ee	In Situ (S)-I 61% Yield 4f, 7:1 dr, 86% ee 66% Yield 4f, 8:1 dr, 98% ee

Alcohol Aldehyde	Preformed (S)-I 71% Yield 4g, >20:1 dr, 99% ee 71% Yield 4g, >20:1 dr, 98% ee	Preformed (S)-I^b 71% Yield 4h, >20:1 dr, 96% ee 66% Yield 4h, >20:1 dr, 99% ee	Preformed (S)-I 76% Yield 4i, 15:1 dr, 97% ee 76% Yield 4i, >20:1 dr, 99% ee
Alcohol Aldehyde	In Situ (S)-I 69% Yield 4g, 7:1 dr, 98% ee 71% Yield 4g, 11:1 dr, 98% ee	In Situ (S)-I no product observed	In Situ (S)-I 73% Yield 4i, 7:1 dr, 95% ee 88% Yield 4i, 7:1dr, 95% ee

Cited yields are of material isolated by silica gel chromatography. Enantiomeric excess was determined by chiral stationary phase HPLC analysis through comparison of reaction products to racemic diastereomeric mixtures. For assignment of relative and absolute stereochemistry, see reference ^2c. See experimental section for further details.

70 °C.