Method for producing binaphthyl carboxylic acid
AssigneeHonshu Chemical Industry Co., Ltd.
InventorsDaichi Sakuma, Takeru Suto
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Abstract
A method for producing 2,2′-bis(carboxymethoxy)-1,1′-binaphthyl includes performing steps (i) to (iv) below in sequence using a 2,2′-bis(alkoxycarbonylmethoxy)-1,1′-binaphthyl as a starting material: (i) a hydrolysis reaction step, (ii) a step of distilling off a resulting alcohol represented by formula (3) above from a reaction system, (iii) a step of acidifying a reaction solution, and (iv) a step of precipitating 2,2′-bis(carboxymethoxy)-1,1′-binaphthyl in the presence of an organic solvent.
Claims2
A method for producing 2,2′-bis(carboxymethoxy)-1,1′-binaphthyl represented by formula (2) below, comprising performing steps (i) to (iv) below in sequence using a 2,2′-bis(alkoxycarbonylmethoxy)-1,1′-binaphthyl represented by formula (1) below as a starting material:
- (i) a hydrolysis reaction step,
- (ii) a step of distilling off a resulting alcohol represented by formula (3) below from a reaction system,
- (iii) a step of acidifying a reaction solution, and
- (iv) a step of precipitating 2,2′-bis(carboxymethoxy)-1,1′-binaphthyl in the presence of methyl isobutyl ketone as an organic solvent while cooling the reaction solution at a cooling rate of 5° C. to 15° C. per hour, wherein
- in step (i), a mixed solvent of methyl isobutyl ketone and water is used as a reaction solvent, and
- step (ii) comprises, after adding methyl isobutyl ketone to the reaction system, distilling off water and methyl isobutyl ketone together with the alcohol represented by formula (3) from the reaction system at a temperature of 70° C. to 90° C. under reduced pressure by a distillation quantity of 200 to 450 parts by weight, relative to 100 parts by weight of the 2,2′-bis(alkoxycarbonylmethoxy)-1,1′-binaphthyl represented by formula (1);
- wherein each R independently represents an alkyl group having 1 to 8 carbon atoms,
- ROH (3)
- wherein R represents an alkyl group having 1 to 8 carbon atoms.
Dependencies are inferred from the claim text.