With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.4629-80-5,1,3-Dimethylpiperidin-4-one,as a common compound, the synthetic route is as follows.
B. Preparation of the Piperidinol The 3-bromo-i-propoxybenzene (200 g, 0.08703 mol) was combined with THF (tetrahydrofuran) (540 ml) under nitrogen and cooled to about -75 C. n-Butyllithium (565 ml, 0.8306 mol) was added dropwise while maintaining the mixture at less than -70 C. After 2 hours 1,3-dimethyl-4-piperidone (106.7 g, 0.8389 mol) was added while maintaining the temperature of the mixture between -80 C. and -70 C. After stirring for 2 hours at -70 C., the reaction mixture was then added to 6N HCl (280 ml) while maintaining the temperature at 20-25 C. The pH was adjusted to 1 with 12 N HCl. The aqueous layer was isolated and heptane (320 ml) was added to it along with 50% NaOH (48 ml, to pH of 13-14). The resulting mixture was allowed to stand overnight. The mixture was heated to 45-50 C. and the upper layer was separated. The remaining aqueous layer was extracted with heptane (320 ml) at 45-50 C. The combined organic fractions were washed with de-ionized water (120 ml) at 45-50 C. The resulting organic layer was vacuum distilled at a pot temperature of about 55 C. at 100 mmHg to remove part of the heptane. Crystallization from heptane provided 151.8 g of the named product. Melting point 75.0-76.0 C. Analysis: Calc. for (C16 H25 NO2): C, 72.97; H, 9.57; N, 5.32. Found: C, 72.87; H, 9.56; N, 5.25.
4629-80-5, Big data shows that 4629-80-5 is playing an increasingly important role.
Reference：
Patent; Eli Lilly and Company; US5136040; (1992); A;,
Piperidine – Wikipedia
Piperidine | C5H11N – PubChem