25714-71-0

4-Hydroxybutanal forms a cyclic hemiacetal when the hydroxyl oxygen add to the aldehyde group. Methanol reacts with this cyclic hemiacetal to form 2-methoxytetrahydrofuran which is our desired product.2-Methoxytetrahydrofuran is a cyclic acetal. The hydroxyl oxygen of 4-Hydroxybutanal reacts with the aldehyde to form cyclic ether linkage.

The 4-hydroxybutanal which is produced as the high yield product of the invention hydroformylation process can be separated and recovered by conventional distillation procedures. It is highly preferred, however, to subject the hydroformylation product mixture to aqueous phase extraction. Surprisingly it was found that water is capable of extracting 4-hydroxybutanal from the product mixture substantially to the exclusion of the other product mixture components. In a commercial scale operation, an aqueous phase stream can be contacted countercurrently and continuously with reaction product effluent from the hydroformylation reaction zone. The resultant aqueous phase containing 4-hydroxybutanal is an excellent vehicle for subsequent processing procedures, such as hydrogenation of 4-hydroxybutanal with Raney nickel to produce valuable 1,4-butanediol.
literature source US04064145

[1] QINGYONG MENG Ming B H Chenggen Zhang. A theoretical model study on the cyclic reaction of 4-hydroxybutanal catalyzed by Br?nsted acid[J]. Canadian Journal of Chemistry, 2009, 68 1: 1610-1619. DOI:10.1139/V09-126.
[2] LUDMILA LEITE. Transformation of 4-hydroxybutanal over porcelain[J]. Journal of Molecular Catalysis A: Chemical, 1999, 144 2: Pages 323-328. DOI:10.1016/S1381-1169(98)00382-3.
[3] https://patents.google.com/patent/CN114149312A/en