(455e) Understanding The Interplay Between Dynamics And Reactivity Of Organic Layers Deposited On Mcm-41
AIChE Annual Meeting
2007 Annual Meeting
Enantioselective Catalysis Topical
Aspects of Chiral Catalysis
Wednesday, November 7, 2007 - 5:10pm to 5:35pm
The area of organocatalysis is one that has grown dramatically in recent years. Organic layers attached to model substrates, as heterogeneous catalysts, offer potential opportunities for a deeper mechanistic understanding of organocatalysis. This talk will present an overview of our recent work in using solid-state NMR to probe dynamics and local structure in these systems and rationalize reactivity in the context of the NMR data. First, we will present results of 2H NMR measurements that study the rotational dynamics of several groups attached to MCM-41, including trimethylsilyl groups, deuterated substituent groups of secondary amines (e.g. labeled benzylamine, methylamine, and piperazine), and surface tethered amino acids (e.g. lysine, serine, hydroxyproline) wherein the amine groups have been deuterated via H/D exchange. We will then present results from catalytic testing, including the Aldol and Henry reaction. Two points will be emphasized: the relationship between dynamics and activity, and in the case of the amino-acid supported catalysts, the relationship between the functional group pairing and activity/selectivity (ee).