Enantiomerically enriched, polycrystalline molecular sieves
This disclosure describes enantiomerically enriched chiral molecular sieves and methods of making and using the same. In some embodiments, the molecular sieves are silicates or germanosilicates of STW topology.
1. A method of preparing an enantiomerically enriched organic product, the method comprising converting an achiral organic precursor to the enantiomerically enriched organic product in a chemical reaction that is catalyzed by a microporous crystalline silicate catalyst,
wherein the microporous crystalline silicate catalyst comprises:
(a) an oxide of silicon; and optionally
(b) one or more oxides of aluminum, boron, cerium, gallium, germanium, hafnium, iron, tin, titanium, indium, vanadium, zirconium, or a combination thereof; and
wherein microporous silicate catalyst has a STW topology and is in the form of an enantiomerically enriched powder comprising two enantiomers of the crystalline microporous silicate catalyst of STW topology; and
wherein the enantiomerically enriched powder exhibits an enantiomeric excess of one enantiomer of the microporous silicate catalyst of STW topology over the other enantiomer of the microporous silicate catalyst of STW topology of at least 10%.
2. The method of claim 1 , wherein the chemical reaction is:
(a) an asymmetric epoxide ring-opening reaction;
(b) an asymmetric hydrogenation reaction;
(c) an asymmetric dihydroxylation reaction;
(d) an asymmetric oxyamination reaction;
(e) an asymmetric hydride transfer reaction;
(f) an asymmetric hydrosilylation reaction;
(g) an asymmetric hydroboration reaction;
(h) an asymmetric hydrovinylation reaction;
(i) an asymmetric hydroformylation reaction;
(j) an asymmetric hydrocarboxylation reaction;
(k) an asymmetric isomerization reaction;
(l) an asymmetric allylic alkylation reaction;
(m) an asymmetric cyclopropanation reaction;
(n) an asymmetric Diels-Alder reaction;
(o) an asymmetric Heck reaction;
(p) an asymmetric Aldol reaction;
(q) an asymmetric Michael addition reaction; or
(r) an asymmetric epoxidation reaction.
3. The method of claim 1 , wherein the chemical reaction is an asymmetric epoxide ring-opening reaction.
4. The method of claim 1 , wherein the chemical reaction is an asymmetric hydrogenation reaction.
5. The method of claim 2 , wherein the chemical reaction is an asymmetric dihydroxylation, oxyamination, hydride transfer, hydrosilylation, hydroboration, hydrovinylation, hydroformylation, hydrocarboxylation, isomerization, allylic alkylation, cyclopropanation, Diels-Alder, Heck, Aldol, Michael addition, or epoxidation reaction.
6. The method of claim 1 , wherein the microporous silicate catalyst of STW topology is a pure silicate, an aluminosilicate, a borosilicate, a germanosilicate, a titanosilicate, a germanoaluminosilicate, or a germanotitanosilicate.
7. The method of claim 1 , wherein the microporous silicate catalyst of STW topology is predominantly in a hydrogen form.
8. The method of claim 1 , wherein the microporous silicate catalyst of STW topology contains at least one alkali metal cation or alkaline earth metal cation in its micropores.
9. The method of claim 1 , wherein the microporous silicate catalyst of STW topology contains a transition metal or transition metal oxide in its micropores.
10. The method of claim 1 , wherein the microporous silicate catalyst of STW topology contains Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Be, Al, Ga, In, Zn, Ag, Cu, Fe, Co, Ni, Cd, Ru, Rh, Pd, Pt, Au, Hg, La, Ce, Pr, Nd, Pm, Sm, Eu, or R 4-n N + H n cations, in its micropores, where R is alkyl, and n=0-4.
11. The method of claim 1 , wherein the enantiomerically enriched powder exhibits an enantiomeric excess of an S-STW enantiomer of at least 75%.
12. The method of claim 1 , wherein the enantiomerically enriched powder exhibits an enantiomeric excess of an R-STW enantiomer of at least 75%.
13. A method of preparing an enantiomerically enriched organic product, the method comprising selectively adsorbing one enantiomer of a chiral organic molecule from a stereoisomeric mixture of the organic molecules by contacting the stereoisomeric mixture of the organic molecules with an enantiomerically enriched powder of a crystalline microporous silicates,
wherein the microporous crystalline silicate comprises:
(a) an oxide of silicon; and optionally
(b) one or more oxides of aluminum, boron, cerium, gallium, germanium, hafnium, iron, tin, titanium, indium, vanadium, zirconium, or a combination thereof; and
wherein microporous silicates have a STW topology, and
wherein the form of an enantiomerically enriched powder comprising two enantiomers of the crystalline microporous silicate of STW topology and exhibits an enantiomeric excess of one enantiomer of the microporous silicate catalyst of STW topology over the other enantiomer of the microporous silicate catalyst of STW topology of at least 10%.
14. The method of claim 13 , wherein the enantiomerically enriched powder exhibits an enantiomeric excess of an S-STW enantiomer of at least 75%.
15. The method of claim 13 , wherein the enantiomerically enriched powder exhibits an enantiomeric excess of an R-STW enantiomer of at least 75%.