Sulfuric Acid → (R)-5-Hydroxy-1,3-dihydrospiro[indene-2,3'-pyrrolo[2,3-b]pyridin]-2'(1'H)-one
Reaction equation
N([O-])=O.[Na+].N[C:6]1[CH:7]=[C:8]2[C:21](=[CH:22][CH:23]=1)[CH2:20][C@:10]1([C:18]3[C:13](=[N:14][CH:15]=[CH:16][CH:17]=3)[NH:12][C:11]1=[O:19])[CH2:9]2.[OH:24]S(O)(=O)=O>O>[OH:24][C:6]1[CH:7]=[C:8]2[C:21](=[CH:22][CH:23]=1)[CH2:20][C@:10]1([C:18]3[C:13](=[N:14][CH:15]=[CH:16][CH:17]=3)[NH:12][C:11]1=[O:19])[CH2:9]2Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
A solution of sodium nitrite (275 mg, 3.98 mmol) in water (1.6 mL) was slowly added to a cooled mixture of (R)-5-amino-1,3-dihydrospiro[indene-2,3′-pyrrolo[2,3-b]pyridin]-2′(1′H)-one (1 g, 3.98 mmol, described in Intermediate 3) in of 10% aqueous H2SO4 (8 mL) at 0° C. The ice bath was removed and the reaction allowed to stir at ambient temperature. The reaction mixture was then placed into a 70° C. oil bath and the bath was heated to 100° C. Bubbling was observed and heating was continued until LCMS indicated that the reaction was complete. The reaction was slowly neutralized by addition of 30% NH4OH (ca. 2 mL) and the precipitate was collected by filtration and washed with water. The solid was then air dried and chromatographed by first mixing with silica and dry loading on a silica gel column. The product was eluted. with (10% MeOH/CH2Cl2). Concentration of the product containing fractions gave the title compound. MS: m/z=253 (M+1).
Workup
- customThe ice bath was removed
- customwas then placed into a 70° C.
- temperaturethe bath was heated to 100° C
- customBubbling
- temperatureheating
- additionThe reaction was slowly neutralized by addition of 30% NH4OH (ca. 2 mL)
- filtrationthe precipitate was collected by filtration
- washwashed with water
- customair dried
- customchromatographed
- additionby first mixing with silica
- customdry loading on a silica gel column
- washThe product was eluted
- additionConcentration of the product containing fractions
Sources & evidence
- ORD record
- ord-fc4dbe978b2a4b3cbeec76b63a8ff28e
- Source dataset
- uspto-grants-2014_07
- Patent number
- US08765759B2
Reaction notes
Loading…