Sciencemadness Discussion Board

Selective cross aldol condensation for enolizable reagents

EverythingAl2O3 - 2-12-2020 at 12:58

I'm looking for a selective aldol/looking to develop one. The closest I've found is linked below. I particularly want to selectively link propanal and 2-iodoethanal together.

I'm thinking an acid catalyst will significantly help for the selectivity. I'm planning on testing Al2O3, L-proline, and maybe a few other mecondensate.

My thought is that the halo aldehyde carbonyl will be too acidic to easily enolize due to difficulties grabbing a proton or lewis acid site limiting the undesired condensates or at least pushing the desired product towards being the major one. I would like to hear if there is something I'm missing about the nature of aldehydes in aldol condensation.
https://pubs.acs.org/doi/10.1021/ja208873k