Phthalide, 6,7-Dimethoxy

D. Taub et al., Tetrahedron 24, 2443 (1968) 3-Hydroxy-5,7-dimethoxy-phthalid (4,6-Dimethyl-phthal-2-al-... 

Esters and lactones can be oxidized at the alcoholic parts to give carboxylic acids with the same number of carbon atoms. 2-Fluoroheptyl acetate is transformed in 78-84% yield into 2-fluoroheptanoic acid by heating for 25 h at 48 °C with nitric acid and acetic acid [472]. 3,5-Dimethoxy-phthalide is converted into 3,5-dimethoxyphthalic acid in 90% yield by treatment with alkaline potassium permanganate at 0 °C for 12 h and at room temperature for 24 h (equation 468) [879]. 

Oxy-3.6-dimethoxy-phthalid 18,164. 5>Oxy-4.6-dimethozy-phthalid 18 I1147. Ftirfurylidenmalons iire tl le8ter 18, 337. 

Paired electrosynthesis of phthalide and p-fert-butyl benzaldehyde (Putter and Hannebaum, 2000) and 2,5 Dimethoxy-2,5-dihydrofuran from furan (Steckhan et al, 2000)... 

This method is remarkably useful for the synthesis of some phthalide alkaloids which have been hitherto prepared by the Bishler-Napieralsky reaction. Condrastine I and II54, for instance, have been prepared from 2-methyl-3,4-dihydro-6,7-dimethoxy-isoquinolinium iodide 52 and 3-bromomeconine 53 in the total yield of 77% (ratio I II = 42 35) 38). 

Condensation of 2,2-dimethoxy-l-methyl pyrrolidine(piperidine) with 1-indanone, 1-tetralone, 4-thiochromanone, butyrolactone, phthalide and substituted 2-oxindoles gives the corresponding enaminoketones614. 

S)-6,7-Dimethoxy-3-[(5/ )-5,6,7,8-tetrahydro-4-methoxy-6-methyl-1,3-dioxolo[4,5-g]isoquinolin-5-yl]phthalide C,2H.3N07 = 413.4 CAS—128-62-1... 

The 7,8-dimethoxy homophthalic anhydride 52 prepared via lithiation of 2,3-di-methoxy N,N-diethylbenzamide has been used to obtain some phthalide isoquinolines, while the 7,8-methylenedioxy homophthalic anhydride 53 has been used to prepare ( ) chelidonine (58) a benzophenthridine alkaloid... 

N-Methyldihydro-5a-paravallarine, 7, 8 3-Methyl-3-(3,4-dimethoxy-l-naphthyl)-phthalide, 270... 

Alkylation at a benzylic position in the ring adjoining a veratryl system has been reported. The carbanion from phthalide in tetrahydrofuran by addition to lithium diisopropylamide in tetrahydrofuran at -70°C was reacted after 20mins. at -35°C by introducing the suspension into 6,7-dimethoxy-2-methyl-... 

Dimethoxy-3-f6.brom.3.oxy-4-methoxy-phenyl].phthalid 18 II199. 

Dimethoxy-3-[4-methoxy-S-methyl-phenyll-phthalid 18 II168. 

Dimethoxy-3-[4-methoxy-3-methyl phenylj-phthalid 18 II169. 8. f-IKmethoxy-3-[2-methoxy-4-methyl phenyl]-phthalld 18 II169. 

Dioxy-6 methoxy-4-methyI-2- [4-meth-oxy i enyl]-benzc yiwiol-(2) 17 II 271. 6.7 Dimetboxy 3>[2.4-dimethoxy-irfienyl]-phthalid 18 I 410. 

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