6-Benzyl-9- Benzylamid

Ceric ammonium nitrate (CAN), CH3CN, H2O, it, 12 h, 96% yield. Benzylamides are not cleaved under these conditions. Some of the methods used to cleave the benzyl group should also be effective for cleavage of the PMB group. Ceric ammonium nitrate is also used to cleave the PMB group from a sulfonamide nitrogen. ... 

Benzyl-l,3-dioxo-l,2,3,4-tetrahydro-j8-carboline (189) was prepared by heating the benzylamide 188 with polyphosphoric acid on a... 

THfluormethansulfonsaure-(benzyl-ethyl-amid) Zu einer Losung von 1,18 g (0,005 mol) Trifluormethansul-fonsaure-benzylamid in 50 ml Aceton gibt man unter Ruhren 0,69 g (0,005 mol) Kaliumcarbonat und dann... 

Beckmann rearrangement of, 729,741 p-Benzoquinone, 745 Benzoylacetone, 865 o-Benzoylbenzoic acid, 728, 739 Benzoyl chloride, 791, 792 Benzoyl glycine, 584 Benzoyl peroxide, 807 determination of, 809 Benzoyl piperidine, 489, 492 P-Benzoylpropionic acid, 728, 737 P-Benzoylpropionitrfle, 911, 912 Benzoyl-p-toluidide, 582, 583 Benzyl acetate, 780, 783 Benzylacetophenone, 726, 734 Benzyl alcohol, 706,711, 811,812,884 N-Benzylamid es 394 table of, 395 ... 

Several different types of linker have been developed that yield amides upon cleavage. These linkers can often also be used to prepare sulfonamides, carbamates, or ureas. There are essentially three different strategies for the release of amides from insoluble supports (a) cleavage of the benzylic C-N bond of resin-bound N-alkyl-N-benzylamides (backbone amide linkers, BAL linkers), (b) nucleophilic cleavage of resin-bound acylating agents with amines, and (c) acylation/debenzylation of resin-bound /V-benzyl-/V,A -dialkylamines. 

Figure 3.18. Acidolytic cleavage of aryl benzyl ethers as competing reaction during the acidolysis of N-benzylamides [212],...

One of the oldest linkers for amides is the (4-methylbenzhydryl)amine linker (MBHA Entry 1, Table 3.11). In contrast to the corresponding benzhydrol linker (which is cleavable by 5% TFA in DCM, 5 min [45]), acidolysis of the benzylic C-N bond of the MBHA linker requires treatment with hydrogen fluoride or a similar acid. As for A-benzylamides, the acid-lability of Al-(diarylmethyl)amides increases with the number of electron-donating substituents on the aryl groups. 

V-Benzylamides of acids from esters. Esters are converted into the N-benzyl-amides of the corresponding acids by heating with benzylamine in the presence of a little ammonium chloride as catalyst ... 

N-Benzylamides are recommended when the corresponding acid is liquid and/or water-soluble so that it cannot itself serve as a derivative. The benzyl-amides derived from the simple fatty acids or their esters are not altogether satisfactory since they are often low melting those derived from most hydroxy acids and from polybasic acids or their esters are formed in good yield and are easily purified. The esters of aromatic acids yield satisfactory derivatives but the method must compete with the equally simple process of hydrolysis and precipitation of the free acid, an obvious derivative when the acid is a solid. The procedure fails with esters of keto acids, sulphonic acids and inorganic acids and some halogenated aliphatic esters. 

The isoquinolines 70 are an important subclass of the tertiary N-benzylamides, and their lithiation and benzylation is an important way of synthesising a range of benzylisoquinoline alkaloids.4849... 

The N-H bond of amides has a pKa of 15-18, an acidity comparable to alcohols and protection of the N-H bond by JV-benzylation is a common ploy. Schemes 8.181 and 8.182 exemplify catalytic hydrogenolyses of N-benzylamides, which were steps in syntheses of Huperzine A71 and AI-77-B (gastroprotective agent),385 respectively. However a number of authors have commented that N-benzylamide groups can be difficult to hydrogenolyse (see below) and therefore these examples may represent particularly favourable cases,... 

O-Benzyl-N-benzyloxycarbonyl- 383 N-Benzyloxycarbonyl- O-aminoacetoxy- 555 N- Benzyloxycarbonyl- O-azidoacetoxy- 555 N-Benzyloxycarbonyl-O-benzyl- 555 3-Phenyl- -athylester 550 3-Phenyl- -benzylamid 403... 

Debenzylation. Benzyl ethers, Ai-benzylamides, and benzyl ester(s) are efficiently... 

Benzylamides were found to be oxidized to the corresponding diacyla-mines in the presence of molecular oxygen, catalytic 48% aq HBr, and Ca(OH)2 under visible light irradiation of a fluorescent lamp (see Scheme 18). This appears to be a convenient protocol for this conversion and the proposed mechanism involves hydrogen abstraction from the benzylic position by the photoproduced bromine atom, oxygen addition to the... 

Iminodipropionic ethyl ester benzylamide heated 3 hrs. at 200-205 and atmospheric pressure with distillation of the resulting ethanol 4-benzyl-czs-2,6-dimethyl-3,5-diketopiperazine. Y 85%. G. Gignarella, J. Med. Ghem. 7, 241 (1964). 

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