摘要 |
Methylolalkanal of the formula II(R=CH2OH, C1-C22-alkyl, aryl or C6-C22-aralkyl) is prepared spe-wise bya) reacting a C2-C24-aldehyde with formaldehyde in the presence of a tertiary amine,b) separating the reaction mixturei) into a bottom fraction comprising the compound of formula II and an incompletely methylolated compound of the formula IIIand a distillate stream comprising unconverted or partially converted starting materials, orii) into an aqueous phase and an organic phase, and recycling the distillate stream or the organic phase to a), andc) subjecting the bottom fraction or the aqueous phasei) to a catalytic or thermal reaction to convert the compound of formula III to the compound of formula II and to a corresponding methylene compound of formula IV(R'=H or R) andii) separating the reaction product into an overhead stream comprising the compound of formula IV and unconverted formaldehyde which is recycled to a), and a bottom fraction comprising the compound of formula II.
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