| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1351018 | Tetrahedron: Asymmetry | 2005 | 5 Pages |
The asymmetric cyanobenzoylation of aldehydes has been carried out for the first time, by reaction with benzoyl cyanide in a process catalysed by either (R)- or (S)-3,3′-bis(diethylaminomethyl)-1,1′-binaphthol BINOLAM–Ti(IV) complexes at room temperature and without additives. The reaction can be described as an overall cyano-O-benzoylation of aldehydes where a Lewis acid–Brönsted base (LABB) dual role for the catalyst induced firstly the key enantioselective hydrocyanation, which is then followed by O-benzoylation furnishing enantioenriched O-benzoyl cyanohydrins.
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(S)-2-(Benzyloxy)-2-phenylacetonitrileC15H12NO2Ee = 68%[α]D25=-7.7 (c 2, CHCl3)Source of chirality: (R)-BINOLAMAbsolute configuration: (S)
(R)-2-(Benzoyloxy)-2-(4-methoxyphenyl)acetonitrileC16H13NO2Ee = 56%[α]D25=+10.9 (c 1, CHCl3)Source of chirality: (S)-BINOLAMAbsolute configuration: (R)
(R)-2-(Benzoyloxy)-2-(4-chlorophenyl)acetonitrileC15H10ClNO4Ee = 58%[α]D25=+9.6 (c 1, CHCl3)Source of chirality: (S)-BINOLAMAbsolute configuration: (R)
(S)-2-(Benzoyloxy)-2-furylacetonitrileC13H9NO3Ee = 55%[α]D25=-2.9 (c 1, CHCl3)Source of chirality: (S)-BINOLAMAbsolute configuration: (S)
(R)-2-(Benzoyloxy)-3-nonenenitrileC16H19NO2Ee = 68%[α]D25=-4.3 (c 0.5, CHCl3)Source of chirality: (S)-BINOLAMAbsolute configuration: (R)
(R)-2-(Benzoyloxy)octanenitrileC15H19NO2Ee = 58%[α]D25=+10.1 (c 0.7, CHCl3)Source of chirality: (S)-BINOLAMAbsolute configuration: (R)
(R)-2-(Benzoyloxy)-4-phenylbutanenitrileC17H16NO2Ee = 65%[α]D25=+13.9 (c 2, CHCl3)Source of chirality: (S)-BINOLAMAbsolute configuration: (R)
