Phthalimidines phthalimides

Electrolytic reduction of phthalimide and of phthalimidines which are at an oxidation level above that of isoindole, proceeds through the isoindole to the isoindoline stage, which is then stable to further... 

Phthalimide was hydrogenated catalytically at 60-80° over palladium on barium sulfate in acetic acid containing an equimolar quantity of sulfuric or perchloric acid to phthalimidine [7729]. The same compound was produced in 76-80% yield by hydrogenation over nickel at 200° and 200-250 atm [43 and in 75% yield over copper chromite at 250° and 190 atm [7730]. Reduction with lithium aluminum hydride, on the other hand, reduced both carbonyls and gave isoindoline (yield 5%) [7730], also obtained by electroreduction on a lead cathode in sulfuric acid (yield 72%) [7730]. 

Preliminary investigations showed that the replacement of one phthalimide in W84 with the benzylidene phthalimi-dine moiety results in an increase in potency in comparison to W84 which could be further enhanced by the replacement of the second phthalimide with benzylidene phthalimidine moiety (Holzgrabe et al., 1997). Similar observations were made for the stepwise replacement of the phthalimide with the above discussed optimal naphthal-imide substituent. The symmetrical compound appears to be about 100 times more potent than W84 and seems to be the most active compound reported till now. It is interesting to find out in the next step whether an asymmetrical compound composed of an hexane-bisammonium-chain connecting a benzylidene phthalimidine and a naphthalim-... 

The general utility of this reaction remains in doubt, however. Reduction of JV-(pent-4-enyl)phthalimide gives a mixture containing about equal amounts of the isoindole and isoindoline, with a smaller amount of the phthalimidine.55... 

A route to cyclic peptide mimetics has been developed using the SET-induced photochemical cyclization of the phthalimide derivatives (119). This process affords the cyclized compounds (120) in excellent yields (85-91 %). Hydroxy-phthalimidines are the products formed from the photochemical decarboxylation of a series of alkyl carboxylates in the presence of V-substituted phthalimides. The photochemical addition of a-silyl electron-donor systems, such as Et2NCH2SiMe3, to V-methylthiophthalimide takes plaee in polar solvents such as acetonitrile. 

Benzylic oxidation of A(-substituted phthalimidines by treatment with 2,2 -bipyridinium chlorochromate/m-CPBA affords phthalimides in good yields. ... 

Dioinr-7-methyl-isochinolin 21,180. N-Aoetyl-oxindol 21, 284, II260. N-Aoetyl-phthalimidin 21, 287, U 252. N-Phenyl-suooinimid 21, 374,1329. II303. X-Athyl-iaatin 21, 448,1355. X-Athyl-phthalimid 21, 461,1363, H 3tf. 2.3.Dioxo-l-methyl-1.2.3.4-tetrshydro-... 

Chromium trioxide/sulfuric acid Phthalimides from phthalimidines... 

Pyridine s. under H2S Zinc/acetic acid Preferential reduction of hindered carbonyl groups Phthalimidines from phthalimides... 

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