Did You Know...
...Chester Carlson was a patent agent who tired of having to make multiple copies of patent applications using the only duplication method available at the time: carbon paper. In 1959 he came up with a new copying system and took it to IBM for evaluation. The "experts" at IBM determined potential sales to be only 5,000 units because people wouldn't want to use a bulky machine when they had carbon paper. Carlson's invention was the xerography process, the company founded on the system is Xerox.
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US Patent 5773632 - Process for the preparation of the enol lactone of 2-oxocyclohexlidene acetic acid and application to the preparation of 2-cuomaranone
US Patent Issued on June 30, 1998
Estimated Patent Expiration Date:
June 26, 2017Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
Estimated Patent Expiration Date:
June 26, 2017Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.AbstractA process for the preparation of the enol lactone of 2-oxocyclohexylidene acetic acid wherein(i) glyoxylic acid is allowed to react with cyclohexanone in the presence of a halogen acid in order to obtain a crude reaction product B1, then(ii) said crude reaction product B1 is allowed to react, after solubilisation in an organic solvent, in the presence of a strong acid soluble in said organic solvent or of strongly acid resins, in order to obtain the enol lactone of 2-oxocyclohexylidene acetic acid which is isolated if desired,and application to the preparation of 2-coumaranone. | InventorsAssigneeApplicationNo. 883594 filed on 06/26/1997US Classes:549/307, The other cyclo of the bicyclo ring system is benzene (e.g., phthalides, etc.)549/462, Bicyclo ring system having the hetero ring as one of the cyclos549/471Plural double bonds between ring members of the hetero ringField of Search549/307, The other cyclo of the bicyclo ring system is benzene (e.g., phthalides, etc.)549/462, Bicyclo ring system having the hetero ring as one of the cyclos549/471Plural double bonds between ring members of the hetero ringExaminersPrimary: Trinh, Ba K.Attorney, Agent or FirmUS Patent References3862133Foreign Patent References
International ClassC07D 307/83Foreign Application Priority Data1996-07-09 FR |
