2-Acetylbutyrolactone → 9-(Benzyloxy)-3-(2-chloroethyl)-2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one
Reaction equation
P(Cl)(Cl)([Cl:3])=O.[C:6]1([CH2:12][O:13][C:14]2[C:15]([NH2:20])=[N:16][CH:17]=[CH:18][CH:19]=2)[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1.[C:21]([CH:24]1[CH2:28][CH2:27][O:26][C:25]1=O)(=O)[CH3:22].[OH-].[NH4+]>CC1C=CC=CC=1>[Cl:3][CH2:27][CH2:28][C:24]1[C:25](=[O:26])[N:16]2[CH:17]=[CH:18][CH:19]=[C:14]([O:13][CH2:12][C:6]3[CH:7]=[CH:8][CH:9]=[CH:10][CH:11]=3)[C:15]2=[N:20][C:21]=1[CH3:22]Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 50 °C
Procedure
To a stirred mixture of 84 parts of phosphoryl chloride and 540 parts of methylbenzene were added 20 parts of 3-(phenylmethoxy)-2-pyridinamine. The mixture was stirred at 50° C. and 22 parts of 3-acetyl-4,5-dihydro-2(3H)-furanone were added. The reaction mixture was stirred for 5 hours at 90° C. Another portion of 22 parts of 3-acetyl-4,5-dihydro-2(3H)-furanone was added and stirring was continued for 30 minutes at 90° C. The solution was allowed to stand overnight at 90° C. The whole was poured into crushed ice and treated with an ammonium hydroxide solution 25%. The product was extracted with trichloromethane. The extract was dried, filtered and evaporated. The residue was purified by column chromatography over silica gel using a mixture of trichloromethane and methanol (98:2 by volume) as eluent. The pure fractions were collected and the eluent was evaporated. The residue was stirred in 2-propanol. The product was filtered off, washed with a mixture of 2-propanol and 1,1′-oxybisethane and dried at 50° C., yielding 20.5 parts (62.3%) of 3-(2-chloroethyl)-2-methyl-9-(phenylmethoxy)-4H-pyrido[1,2-a]pyrimidin-4-one; mp. 141.1° C. (intermediate 1) b) A mixture of 3.3 parts of 3-(2-chloroethyl)-2-methyl-9-(phenylmethoxy)-4H-pyrido[1,2-a]pyrimidin-4-one and 120 parts of methanol was hydrogenated at normal pressure and at room temperature with 2.0 parts of palladium-on-charcoal catalyst 10%. After the calculated amount of hydrogen was taken up, the catalyst was filtered off and the filtrate was evaporated to dry, yielding 2.4 parts (99%) of 3-(2-chloroethyl)-6,7,8,9-tetrahydro-9-hydroxy-2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one as an oily residue. (intermediate 2)
Workup
- stirringThe reaction mixture was stirred for 5 hours at 90° C
- stirringstirring
- waitto stand overnight at 90° C
- additionThe whole was poured
- custominto crushed ice
- extractionThe product was extracted with trichloromethane
- customThe extract was dried
- filtrationfiltered
- customevaporated
- customThe residue was purified by column chromatography over silica gel using
- additiona mixture of trichloromethane and methanol (98:2 by volume) as eluent
- customThe pure fractions were collected
- customthe eluent was evaporated
- stirringThe residue was stirred in 2-propanol
- filtrationThe product was filtered off
- washwashed with a mixture of 2-propanol and 1,1′-oxybisethane
- customdried at 50° C.
Sources & evidence
- ORD record
- ord-60849242095a4e01abed225e775f22a0
- Source dataset
- uspto-grants-2001_11
- Patent number
- US06320048B1
Reaction notes
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