NeoACat

The aim of this program is the development of several new class of chiral acid catalyst. The desired structures are based on sulfonic acids involving C2 asymmetrical elements (pentasubstituted benzene sulfonic acids derivatives). The preparation of those acids is expected to be facilitated by preliminary unpublished results obtained in our laboratory and should lead to a versatile synthesis of this original class of molecules. Furthermore, progress regarding the synthetic plan would improve dramatically the easiness of the modulation of the stereo-electronic properties of the targeted acids. Thus our first goal would be to capitalize our accumulated knowledge and create a small library of those catalysts. In a second part those catalysts will be tested in a series of reaction where traditionally chiral phosphoric acids derived from BINOL are known to behave sluggishly, according to their intrinsic limited acidity (Mannich and aldol reactions, resolution of alcohol through a stereoablative elimination reaction, protonation of hindered silyl ketene acetals). In a final and third part, innovative way to create asymmetry will be evaluated based on the unique opportunity offered by the original scaffold developed in the program. Various conceptually new chiral silyl Lewis acids will be prepared and tested in important transformations (Diels Alder, Mukaiyama aldol).