Patent classifications
C07C61/15
NEW METHOD FOR SYNTHESIZING 2-FLUOROCYCLOPROPANE CARBOXYLIC ACID
Disclosed is a new method for synthesizing 2-fluorocyclopropanecarboxylic acid comprising: 1) performing reaction of 1,1-dichloro-1-fluoroethane with thiophenol in the presence of an alkali, to produce a phenyl sulfide intermediate; 2) performing oxidation reaction of the phenyl sulfide intermediate with Oxone; 3) performing elimination reaction of the product of Step 2) in the presence of an alkali, to obtain 1-fluoro-1-benzenesulfonyl ethylene; 4) performing addition reaction of the 1-fluoro-benzenesulfonyl ethylene with ethyl diazoacetate in the presence of a catalyst, to obtain a cyclopropane intermediate; 5) performing elimination reaction of the cyclopropane intermediate in the presence of an alkali before acidification, to obtain 2-fluorocyclopropanecarboxylic acid. Herein, the synthetic route is short, used materials are bulk commodities, and raw materials are inexpensive and readily available. The process can be safely scaled up by replacing commonly used mCPBA reagents with Oxone. Further, reaction yield is improved, production cost is greatly reduced, and operation is simplified.
NEW METHOD FOR SYNTHESIZING 2-FLUOROCYCLOPROPANE CARBOXYLIC ACID
Disclosed is a new method for synthesizing 2-fluorocyclopropanecarboxylic acid comprising: 1) performing reaction of 1,1-dichloro-1-fluoroethane with thiophenol in the presence of an alkali, to produce a phenyl sulfide intermediate; 2) performing oxidation reaction of the phenyl sulfide intermediate with Oxone; 3) performing elimination reaction of the product of Step 2) in the presence of an alkali, to obtain 1-fluoro-1-benzenesulfonyl ethylene; 4) performing addition reaction of the 1-fluoro-benzenesulfonyl ethylene with ethyl diazoacetate in the presence of a catalyst, to obtain a cyclopropane intermediate; 5) performing elimination reaction of the cyclopropane intermediate in the presence of an alkali before acidification, to obtain 2-fluorocyclopropanecarboxylic acid. Herein, the synthetic route is short, used materials are bulk commodities, and raw materials are inexpensive and readily available. The process can be safely scaled up by replacing commonly used mCPBA reagents with Oxone. Further, reaction yield is improved, production cost is greatly reduced, and operation is simplified.
Radiolabelling Process
The present invention relates to a novel composition comprising 1-amino-3-[.sup.18F]-fluorocyclobutanecarboxylic acid ([.sup.18F]-FACBC) wherein said composition has certain superior properties in comparison with known compositions comprising [.sup.18F]-FACBC. Also provided by the invention is a method to obtain said composition.
Radiolabelling Process
The present invention relates to a novel composition comprising 1-amino-3-[.sup.18F]-fluorocyclobutanecarboxylic acid ([.sup.18F]-FACBC) wherein said composition has certain superior properties in comparison with known compositions comprising [.sup.18F]-FACBC. Also provided by the invention is a method to obtain said composition.
Radiolabelling process
The present invention relates to a novel composition comprising 1-amino-3-[.sup.18F]-fluorocyclobutanecarboxylic acid ([.sup.18F]-FACBC) wherein said composition has certain superior properties in comparison with known compositions comprising [.sup.18F]-FACBC. Also provided by the invention is a method to obtain said composition.
Radiolabelling process
The present invention relates to a novel composition comprising 1-amino-3-[.sup.18F]-fluorocyclobutanecarboxylic acid ([.sup.18F]-FACBC) wherein said composition has certain superior properties in comparison with known compositions comprising [.sup.18F]-FACBC. Also provided by the invention is a method to obtain said composition.
STEREOSELECTIVE PREPARATION OF TRANS HALO CYCLOBUTANE
The present invention relates to stereoselective process for the preparation of a compound having formula (2) and (1) wherein X is defined in the specification.
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STEREOSELECTIVE PREPARATION OF TRANS HALO CYCLOBUTANE
The present invention relates to stereoselective process for the preparation of a compound having formula (2) and (1) wherein X is defined in the specification.
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