Diisobutylaluminum hydride reductions revitalized: a fast, robust, and selective continuous flow system for aldehyde synthesis.
A continuous flow system for the multiparameter (flow rate, temperature, residence time, stoichiometry) optimization of the DIBALH reduction of esters to aldehydes is described. Incorporating an in-line quench (MeOH), these transformations are generally complete in fewer than 60 s. Mixing of the DIBALH and ester solutions was observed to be an exceptionally critical parameter for optimum results. This system thus provides general guidelines based on the structure of the ester for selective reduction of an ester without overreduction.
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Damien
D
Webb
Timothy F
TF
Jamison
D000447:Aldehydes / Q000138:chemical synthesis*; D004952:Esters / Q000737:chemistry; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D013997:Time Factors
D000447:Aldehydes; D004952:Esters; D009942:Organometallic Compounds; C035719:diisobutylaluminum