34 results about "Cycloheptanone" patented technology

A method for preparing cycloheptanone from cyclohexanone through one step comprises the following steps: using diazomethane as a reagent to prepare a saturated low alcohol solution, adding cyclohexanone and a diluted acid catalyst to a diazomethane alcohol solution, carrying out a slow addition ring expansion reaction at 10-50 DEG C, and carrying out water vapor distillation to prepare crude cycloheptanone; and rectifying the crude cycloheptanone to obtain cycloheptanone. A saturated C4 or less low alcohol solution of diazomethane is prepared through the following steps: reacting hydrochloric acid with a methylamine solution, adding urea, adding a saturated sodium carbonate solution, carrying out a refluxing reaction, adding diluted sulfuric acid, reacting sulfuric acid with a sodium nitrite solution, adding a strong alkali solution to generate a diazomethane gas, introducing the diazomethane gas to a cooled receiving bottle provided with the C4 or less low alcohol. The method has the advantages of short synthetic route, simplicity in operation, environmental protection, high product yield, substantial reduction of the cost, and high facilitation of industrial production.

The invention discloses a chiral N-heterocyclic carbene catalyst as well as a preparation method and application thereof, and belongs to the technical field of organic chemistry. The preparation method of the chiral N-heterocyclic carbene catalyst specifically comprises the following steps: adding N-bromo-succinimide and p-toluenesulfonic acid into a round-bottom flask, dissolving the N-bromo-succinimide and p-toluenesulfonic acid with DCM, adding 1eq of cycloheptanone 1, and reacting at room temperature overnight; after the reaction is completed, concentrating and purifying the reactant to obtain alpha-bromo-cycloheptanone 2; then weighing 1g of montmorillonite, 10mmol of p-methylaniline and 40mmol of phenylacetylene, carrying out solvent-free reaction at 140 DEG C for 8 hours, cooling the reaction product to room temperature, filtering the reaction product, washing the reaction product with diethyl ether, collecting filtrate, concentrating and purifying the filtrate to obtain a compound 5, carrying out asymmetric hydrogenation reduction on the compound 5, and carrying out multi-step reaction on the compound 5 and alpha-bromo-cycloheptanone 2 to synthesize a target compound 7. The method is high in operability, novel in synthetic route and high in yield. The method can be successfully applied to the amide far-end C (sp3)-H activation tandem cyclization reaction, realizes asymmetric catalysis, and has a wide market application prospect.