Phenyl amido derivatives

Aryloxybutyramides (effectively amido derivatives at the benzylic position in phenyl isopropyl ether) readily formed from 2-bromo-iso-butyramide and a variety of phenoxides in dioxane undergo the Smiles rearrangement in dimethylformamide containing 1,3-dimethyltetrahydropyrimidin-2(1H)-one (DMPU) solution and sodium hydride to form substiuted acetanilides with yields in the range 60-90%. Thence by hydrolysis aromatic amines are formed in good yields (ref. 168). 

Oxazepam (116) can be converted into a range of 3-(disubstituted-amino) derivatives, in moderate yield, by its reaction with the appropriate 2-amino-4,5-dihydro-l,3,2-dioxaphosphole. A direct route to the 3-amino-derivatives has also been reported.l,3-Dihydro-2//-l,4-benzodiazepin-2-ones react with most isocyanates to give the 1-carbamoyl derivative however, (114), on reaction with trichloroacetyl isocyanate and subsequent hydrolysis, gave the 3-amido-derivative. The latter has been converted into a range of 3-esters.Continuing work on the electrolytic reduction of 2,3-dihydro-l,4-diazepinium salts has shown that the AW-dibenzyl-6-phenyl-compound gives a diazepine dimer and an unexpected rearrangement product, which is 1,4-di-imidazolidinyl-butadiene. ... 

An earlier report (Keuberger and Pitt-Rivers, 1939) that methyl 2-formamido-2-dooxy-/J-D-glucopyranoside wa.s hydrolyzed as fast as the 2-acet.amido derivatives by extracts of Helix pomaiia, could not be substantiated using the corresponding phenyl glycosides (Greig, 1960). 

The synthesis of enantiopure thiazolines has been reported. The mixture of enantiomerically pure diastereoisomeric amido selenides 64, obtained from the reaction of camphorselenyl sulfate with trans alkenes, when treated with Lawesson s reagent affords a mixture of two thioamide derivatives 65a and 65b. The two diastereoisomeric thioamide selenides were easily separated by chromatography, each was then treated with phenyl selenyl chloride which caused deselenylation to occur in a stereospecific manner furnishing the thiazolines 66a and 66b in an enantiopure form <02TA429>. 

A series of interesting derivatives was prepared21,69 starting from phosphoranes having maleimido, amido, and nitryl functions. These products were 2,4 3,5-di-0-benzylidene-l-deoxy-l-(2,5-dioxo-3-pyr-rolylidene)-D-ribitol (99a), its N-phenyl derivative (99b), 2,4-0-benzylidene-1 -deoxy- l-(2,5-dioxo-3-pyrrolylidene)-D-ribitol (99c), 4,6 5,7-di-0-benzylidene-2,3-dideoxy-D-nbo-hept-2-enonamide (100), 2,3-dideoxy-D-giuco-oct-2-enonamide 4,5,6,7,8-pentaacetate (101), 4,6 5,7-di-0 - benzylidene - 2,3 - dideoxy - D - ribo-hept-2-enononitrile (102), and 2,3-dideoxy-D-g(uco-oct-2-enononitrile 4,5,6,7,8-pentaacetate (103). Derivatives 99a-99c were prepared for use in the... 

Rearrangement of furazan derivatives were studied by Boschi and coauthors [67]. 4-Phenyl-1,2,5-oxadiazole sulfone 130 (Scheme 45) heated in acetone containing sodium hydroxide rearranged to sulfinic acid derivative 132. After expulsion of SO2,3-acetamido-4-phenylfurazan 133 was formed in 86% yield. Amido-sulfide 131 under similar conditions underwent hydrolysis only to afford the respective acid. 

A magnesium-based catalyst system which employs either a bis(oxazoline) or amido-mono(oxazoline) ligand derived from phenylglycine has been reported to effect an interesting Diels-Alder between unsymmetrical alkylidene 26 and cyclopentadiene (Scheme 23) [79]. The reaction generates a quaternary center and is noteworthy in its ability to preferentially deliver cycloadduct 29, despite a superficial similarity between the two carbonyl substituents (OEt vs. Ph). This selectivity has been rationalized on the basis of an inferred steric preference for the phenyl group to reside perpendicular to the alkylidene, thus creating a marked bias in the diastereomeric transition states [80]. 

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