Aluminium lithium hydride → HCID 86657797, compound

Temperature

0 °C

To a stirred solution of (±)-cis-4-methoxymethoxy-piperidine-1,3-dicarboxylic acid 1-tert-butylester 3-methyl ester (1.98 mmol, 0.5 g) in ether (5 mL) at 0° C. was added LAH powder (50 mg) in one lot and continued stirring at 0° C. for additional 20 min followed 10 min at room temperature. TLC analysis of an aliquot of the reaction mixture showed complete consumption of starting material. The reaction mixture was diluted with ether (5 mL), cooled to 0° C., added ethyl acetate drop-wise followed by saturated sodium sulfate. The organic layer was separated, dried, filtered and concentrated under reduced pressure. The residue was purified by silica gel flash column chromatography eluting with 50% ethyl acetate in hexanes to provide (±)-cis-3-hydroxymethyl-4-methoxymethoxy-piperidine-1-carboxylic acid tert-butyl ester (0.506 g, 93%) as an oil. To a stirred suspension of sodium hydride (4.16 mmol, 0.1 g) in THF (8 mL) at room temperature was added (±)-cis-3-hydroxymethyl-4-methoxymethoxy-piperidine-1-carboxylic acid tert-butyl ester (1.84 mmol, 0.506 g) followed 3-butyl-6-chloro-4-(4-cyclohexyloxy-phenyl)-pyridazine (Example 14, 1.74 mmol, 0.6 g). The resultant reaction mixture was kept stirring at 50-60° C. for 2 h. The reaction mixture was cooled to room temperature and excess NaH was decomposed by addition of methanol drop-wise. This was diluted with ethyl acetate (20 mL), washed with water (5 mL), separated the organic layer, dried, filtered and concentrated under reduced pressure. The resultant residue was purified by flash silica gel chromatography by eluting with 40% ethyl acetate in hexanes to afford (±)-cis-3-[6-butyl-5-(4-cyclohexyloxy-phenyl)-pyridazin-3-yloxymethyl]-4-methoxymethoxy-piperidine-1-carboxylic acid tert-butyl ester (0.93 g, 82% yield) as a light yellow oil.

1. waitfollowed 10 min at room temperature
2. customconsumption of starting material
3. additionThe reaction mixture was diluted with ether (5 mL)
4. temperaturecooled to 0° C.
5. additionadded ethyl acetate drop-wise
6. customThe organic layer was separated
7. customdried
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customThe residue was purified by silica gel flash column chromatography
11. washeluting with 50% ethyl acetate in hexanes

ORD record

ord-ecd0025f559e48fea46e704a0b9bc802

Source dataset

uspto-grants-2014_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08741900B2