Description
2-Methyl-1,3-propanediol, MPD, is produced by Arco with an estimated capacity of about 7000 t/a. The process is designed for the production of 1,4-butanediol as an alternative to Reppe technology and the acetoxylation of butadiene. The raw material propylene oxide is isomerized to allyl alcohol in the fifirst step. Hydroformylation of allyl alcohol gives 4- hydroxybutanal (79 %) and 3-hydroxy-2-methylpropanal (11 %). The last step comprises hydrogenation of the n and iso intermediates to the corresponding diols.
Uses
β-Hydroxyisobutanol is used as a reagent in the synthesis of pyrazolo[1,5-a]pyridinecarbonyl-substituted spirocyclic piperidine ketals as inhibitors of HCV protein NS4B and of hepatitis C viral replication and their lack of cytotoxicity in human cells.
Application
2-Methyl-1,3-propanediol (MDP), with its branched and irregular structure, affords noncrystalline resins. It is used in polyesters for solvent- and waterborne coatings, imparting them lower viscosity than neopentyl glycol, easy processability, good flexibility, weatherability, and toughness. 2-Methyl-1,3-propanediol is used in paints with low content of volatile organic compounds (VOC) as two-component polyurethane coating and coil coating. It is also used in glass-fiber-reinforced unsaturated polyesters and gel coats. MPD is used for chemical modification of polyethylene terephthalate (PET) used in production of fibers and films. Low content of MPD in PET fibers improves the dye uptake and in films it improves clarity, toughness, elongation, and shrinkage. Plasticizers, elastomers, adhesives, cosmetics, and personal care products are other uses of MPD.
Synthesis
Equivalents of asymmetrized 2-methyl-1,3-propanediol are prepared by elaborating compounds obtained in optically active form via non-enzymatic asymmetric synthesis[1].
References
[1]Banfi, L., & Guanti, G. (1993). Asymmetrized 2-Methyl-1,3-propanediol and Its Equivalents: Preparation and Synthetic Applications. Synthesis, 1993(11), 1029–1056.
https://doi.org/10.1055/s-1993-25991
