Formaldehyde → (2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanal
반응식
[C:1]1(=[O:7])[CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1.[OH2:8].[OH2:9].[OH2:10].C([O-])(=O)C.[Pb+2].C([O-])(=O)C.[OH-:20].[Na+].C=[O:23]>>[O:7]=[CH:1][C@@H:6]([C@H:5]([C@@H:4]([C@@H:3]([CH2:2][OH:23])[OH:20])[OH:10])[OH:9])[OH:8]참가 물질
5
반응 조건
- 온도
- 95 °C
실험 절차
1500 g of the 37% formalin solution of Example 1 (18.5 moles formaldehyde) and 491 g of cyclohexanone (5 moles) are heated with stirring to 95° C., followed by the addition of 56 g of a 50% aqueous solution of the formose used as co-catalyst in Example 1 of German Offenlegungsschrift No. 2,639,084 and 15 g of lead acetate trihydrate. The pH-value of the mixture is adjusted to 7.5 by the addition of 10% sodium hydroxide. After the reaction has started (increase in the temperature of the mixture to 100°-102° C.), the pH is kept between 6.5 and 7.0 by the addition of more sodium hydroxide. After about 20 minutes, the reaction is stopped at a residual formaldehyde content of 1.5% by cooling with ice water. Total consumption of 10% sodium hydroxide: 123 g. Most of the lead is precipitated with 10 g of sodium bicarbonate and the solution is fully desalted over ion exchangers after the deposit has been filtered off under suction. 800 g of a modified formose having a water content of 5.8% and a sugar content (expressed as glucose) of 37% are obtained.