5962-96-9Relevant articles and documents
SUBSTITUTED THIAZOLE COMPOUNDS
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Page/Page column 19, (2014/06/24)
The invention is concerned with the compounds of formula (I) and pharmaceutically acceptable salts thereof. In addition, the present invention relates to methods of manufacturing and using the compounds of formula (I) as well as pharmaceutical compositions containing such compounds. The compounds of formula (I) are LMP7 inhibitors and may be useful in treating associated inflammatory diseases and disorders such as, for example, rheumatoid arthritis, lupus and irritable bowel disease.
Succinic anhydrides from epoxides
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Page/Page column 24; 25; 26, (2013/07/25)
Catalysts and methods for the double carbonylation of epoxides are disclosed. Each epoxide molecule reacts with two molecules of carbon monoxide to produce a succinic anhydride. The reaction is facilitated by catalysts combining a Lewis acidic species with a transition metal carbonyl complex. The double carbonylation is achieved in single process by using reaction conditions under which both carbonylation reactions occur without the necessity of isolating or purifying the product of the first carbonylation.
Catalytic double carbonylation of epoxides to succinic anhydrides: Catalyst discovery, reaction scope, and mechanism
Rowley, John M.,Lobkovsky, Emil B.,Coates, Geoffrey W.
, p. 4948 - 4960 (2008/02/03)
The first catalytic method for the efficient conversion of epoxides to succinic anhydrides via one-pot double carbonylation is reported. This reaction occurs in two stages: first, the epoxide is carbonylated to a β-lactone, and then the β-lactone is subsequently carbonylated to a succinic anhydride. This reaction is made possible by the bimetallic catalyst [(CITPP)Al(THF)2]+[Co(CO)4]- (1; CITPP = meso-tetra(4-chlorophenyl)porphyrinato; THF = tetrahydrofuran), which is highly active and selective for both epoxide and lactone carbonylation, and by the identification of a solvent that facilitates both stages. The catalysis is compatible with substituted epoxides having aliphatic, aromatic, alkene, ether, ester, alcohol, nitrile, and amide functional groups. Disubstituted and enantiomerically pure anhydrides are synthesized from epoxides with excellent retention of stereochemical purity. The mechanism of epoxide double carbonylation with 1 was investigated by in situ IR spectroscopy, which reveals that the two carbonylation stages are sequential and non-overlapping, such that epoxide carbonylation goes to completion before any of the intermediate β-lactone is consumed. The rates of both epoxide and lactone carbonylation are independent of carbon monoxide pressure and are first-order in the concentration of 1. The stages differ in that the rate of epoxide carbonylation is independent of substrate concentration and first-order in donor solvent, whereas the rate of lactone carbonylation is first-order in lactone and inversely dependent on the concentration of donor solvent. The opposite solvent effects and substrate order for these two stages are rationalized in terms of different resting states and rate-determining steps for each carbonylation reaction.
