EnCat™ and Other Catalysts

Partnering with Reaxa, Sigma-Aldrich offers a variety of transition metal-based encapsulated catalysts for applications in areas such as Suzuki, Stille, and Heck couplings, carbonylations, hydrogenation, hydrogenolysis, and dihydroxylation.

Coupling Chemistry

Pd(II) EnCat™

Pd(II) EnCat™ covers a versatile range of immobilized palladium acetate catalysts with or without activating ligands contained in a robust, porous polyurea matrix which allow easier, faster and cleaner reaction processes to be developed. The recyclable catalysts have demonstrated superb activity in cross-couplings, Heck couplings, and carbonylations.

Cleaner products	Typically less than 10 ppm Pd in crude product
Cleaner waste streams	Reduced metal losses in Pd EnCat™ processes
Fast, efficient processes	EnCat™ beads filter easily
No plant contamination	Metal and ligands are trapped within the beads
Improved processes	High activity in many types of coupling reactions
Process intensification	Can be used in batch and flow processes

 
Technical Information for Download (PDF format):

1) Pd(0) and Pd(II) EnCat™ Presentation (2.8 MB PDF)
2) Pd(II) EnCat™ Technical Flier (485KB PDF)
3) Pd(II) EnCat™ User Guide (72 KB PDF)
4) ChemFiles 2007 Supplement 1: Encapsulated Catalysts and Metal Scavengers (624 KB PDF)

Cheminar™ 1.1: Pd EnCat™ Technology (click here to view)

References:
1) Ladlow, M et al. Org. Biomol. Chem. 2003, 1, 2419.
2) Ley, S. V. et al. Org. Biomol. Chem. 2004, 2, 611.
3) Ley, S. V. et al. Chem. Commun. 2005, 2175.
4) Pilotti, P. et al. Pharm. Disc. 2005, 5(8), 32.
5) Nájera, C. et al. Tetrahedron 2005, 61, 12168.
6) Ley, S. V. Chem. Eur. J. 2006, 12, 4407.
7) Yamamoto, Y. et al. Synlett 2006, 1027.
8) Ley, S. V. et al. Chem. Commun. 2002, 1132.
9) Ley, S. V. et al. Chem. Commun. 2002, 1134.
10) Ley, S. V. et al. Synlett 2002, 1843.
11) Pears, D. A. et al. Aldrichimica Acta 2005, 38, 23.
12) Leeke, G. A. et al. Org. Process Res. Dev. 2007, 11, 144.
13) Ley, S. V. et al. Synlett 2007, 1251.

LaPCat^TM

The LaPCat^TM kit is an exclusive collection of six palladium and/or copper containing perovskite heterogeneous catalysts for use in a wide range of organic reactions. LaPCat^TM catalysts demonstrate superb catalytic activity in many coupling reactions with a wide variety of substrates.

As shown in the table above, the various LaPCat^TM catalysts have broad application in several important classes of carbon-carbon bond forming reactions.

Technical Information for Download (PDF format):

1) LaPCat^TM Presentation (1.3 MB PDF)
2) LaPCat^TM Technical Flier (365 KB PDF)
3) LaPCat^TM User Guide (287 KB PDF)
4) ChemFiles 2007 Supplement 1: Encapsulated Catalysts and Metal Scavengers (624 KB PDF)

Hydrogenation

Pd(0) EnCat™ 30NP

Pd(0) EnCat™ 30NP is a versatile polymer encapsulated nanoparticulate Pd(0) hydrogenation and transfer hydrogenation catalyst with high chemoselectivity and improved safety profile allowing easier, faster and cleaner processes to be developed. Reaxa’s controlled manufacturing process produces regular palladium(0) nanoparticles stabilized by the polymer matrix within the EnCat™ beads, ensuring that the catalyst performance is extremely reproducible from batch to batch (c.f. palladium on carbon).

Technical Information for Download (PDF format):

1) Pd(0) and Pd(II) EnCat™ Presentation (2.8 MB PDF)
2) Pd(0) EnCat™ 30NP Technical Flier (518 KB PDF)
3) Pd(0) EnCat™ 30NP User Guide (340 KB PDF)
4) Pd(0) EnCat™ 30NP Debenzylation Guide (159 KB PDF)
5) ChemFiles 2007 Supplement 1: Encapsulated Catalysts and Metal Scavengers (624 KB PDF)

Cheminar™ 1.1: Pd EnCat™ Technology (click here to view)

 

References:
1) Ley, S. V. et al. Chem. Comm. 2003, 678.
2) Ley, S. V. et al. Beil. J. Org. Chem. 2006, 2, 15.
3) Ley, S. V. et al. Org. Lett. 2003, 5, 4665.
4) Ley, S. V. et al. Org. Biomol. Chem. 2004, 2, 160.
5) Ley, S. V. et al. Chem. Commun. 2002, 1132.
6) Pears, D. A. et al. Aldrichimica Acta 2005, 38, 23.
7) Quai, M. et al. Tetrahedron Lett. 2007, 48, 1241.

Pt(0) EnCat™ 40

Pt(0) EnCat™ 40 is a versatile hydrogenation catalyst demonstrating high chemoselectivity and improved safety profile over platinum on carbon allowing easier, faster and cleaner processes to be developed. Isolating the active platinum within the polymer matrix has produced an easily-handled and safer alternative to Pt/C. The catalyst is particularly effective for hydrogenation of nitro groups and reductive aminations in the presence of halogens.
 

Technical Information for Download (PDF format):

1) Pt(0) EnCat™ 40 Presentation (323 KB PDF)
2) Pt(0) EnCat™ 40 Technical Flier (43 KB PDF)
3) Pt(0) EnCat™ 40 User Guide (43 KB PDF)
4) ChemFiles 2007 Supplement 1: Encapsulated Catalysts and Metal Scavengers (624 KB PDF)

Dihydroxylation

Os EnCat™ 40

Osmium tetroxide (OsO₄)is known to be one of the most reliable and effective catalysts for oxidative cleavage and dihydroxylation of olefins. However, it is very toxic, volatile and expensive, thus limits its usefulness at large-scale. Os EnCat™ 40 effectively immobilizes and stabilizes osmium tetroxide to produce a safer and easier-to-use catalyst for application in oxidation chemistry.

In the above picture, a vial containing Os EnCat™ 40 placed in the presence of corn oil is unchanged after several months, whereas an equivalent sample of volatile osmium tetroxide quickly reacts to produce black decomposition products, indicating the stability of the encapsulated OsO₄.
 

Technical Information for Download (PDF format):

1) Os EnCat™ 40 Technical Flier (73 KB PDF)
2) Os EnCat™ 40 User Guide (111 KB PDF)
3) ChemFiles 2007 Supplement 1: Encapsulated Catalysts and Metal Scavengers (624 KB PDF)

References:
1) Ley, S. V. et al. Org. Lett. 2003, 5, 185.
2) Borhan, B. et al. Tetrahedron Lett. 2006, 47, 3797.
3) Ley, S. V. et al. Org. Lett. 2003, 5, 185.
4) Ley, S. V. et al. Org. Biomol. Chem. 2003, 1, 3957.