Yield:54732-79-5 100%

Reaction Conditions:

with Adam’s catalyst;hydrogen;acetic acid under 2585.81 Torr; for 216 h;

Steps:

1.2 Step 2: Preparation of cis/trans-dimethyl piperidine-3,5-dicarboxylate

After dissolving the dimethyl pyridine-3,5-dicarboxylate (23.0 g, 118 mmol) obtained in step 1 in 60 mL of acetic acid,Pt2O (2.4 g, 5 mol%) was added and hydrogenated at 50 psi for 9 days. LC-MS instrument [manufacturer: Waters, model name: Acquity Ultra Performance LC; Column manufacturer: Waters, model name: Acquity UPLC BEH C18 1.7 μm, 2.1×50 mm;A solvent system: 0.1% formic acid and 10-100% acetonitrile added water] was used to observe the reaction.After the reaction was completed, the catalyst was removed using a celite pad, and washed with acetic acid.The mixture obtained above was dried under reduced pressure to obtain a cis/trans isomer 1:1 in the form of a colorless oil (23.7 g 100%).The compound obtained above protected the nitrogen atom using Boc (tert-butyloxycarbonyl) without a separate purification process.

References:

KR101577430,2015,B1 Location in patent:Paragraph 0180; 0181; 0187-0189