Patent Number: 6,166,225

Title: Processes for producing dialdehyde monoacetals

Abstract: In a method of producing a dialdehyde monoacetal(s) (III) from dialdehyde(s) (I) and diol(s) (II), the present invention provides a method comprising a first step wherein said dialdehyde(s) (I) and said diol(s) (II) are reacted to produce dialdehyde bisacetal(s) (IV), the amount by mole of said diol(s) (II) being at least twice the amount by mole of said dialdehyde (I) and a second step wherein said dialdehyde bisacetal(s) (IV) is reacted with said dialdehyde (I). The present invention also provides a method of producing a glutaraldehyde monoacetal via reacting 2-Y-3, 4-dihydro-2H-pyran or a ring-substituted derivative thereof with diol. This method comprises a second step reaction wherein glutaraldehyde (iv) which is one of the by-products of the first step reaction is reacted with glutaraldehyde bisacetal (v) which is another by-product of said first reaction. According to the present invention, in the above-mentioned method of producing a glutaraldehyde monoacetal (iii), after the end of the first step reaction, the crude reaction solution is heated at a temperature of from C. to C. to produce the glutaraldehyde monoacetal (iii) from the by-products, low boiling-point components produced from the substituant group Y being removed via distillation.

Inventors: Tanaka; Yasutaka (Ohtake, JP), Uenakai; Hiroaki (Kakogawa, JP), Shimada; Giichi (Hiroshima, JP)

Assignee: Daicel Chemical Industries, Ltd.

International Classification: C07D 317/00 (20060101); C07D 317/26 (20060101); C07D 321/00 ()

Expiration Date: 12/26/2017