Benzoyl groups

The reaction of the o-iodophenol 275 with an alkylallene affords the bcnzo-furan derivative 276[184], Similarly, the reactions of the 6-hydroxyallenes 277 and 279 with iodobenzene afford the tetrahydrofurans 278 and 280. Under a CO atmosphere, CO insertion takes place before the insertion of the allenyl bond, and a benzoyl group, rather than a phenyl group, attacks the allene carbon to give 280. Reaction of iodobenzene with 4,5-hexadienoic acid (281) affords the furanone derivative 282[185]. 

J lie decarboxylation is frequently the most troublesome step in this sequence. Attempts at simple thermal decarboxylation frequently lead to recycliz-ation to the lactam. The original investigators carried out decarboxylation by acidic hydrolysis and noted that rings with ER substituents were most easily decarboxylated[2]. It appears that ring protonation is involved in the decarboxylation under hydrolytic conditions. Quinoline-copper decarboxylation has been used successfully after protecting the exocyclic nitrogen with a phthaloyl, acetyl or benzoyl group[3]. 

The product is a mixed anhydride Acetic acid acts as a nucleophile and substi tutes for chloride on the benzoyl group... 

Heating 2-phenyl-4-benzoyl-l,3,4-thiadiazolium chloride (121) at 200 °C causes the benzoyl group to move to the 2-position as in (122) (68AHC(9)165), probably via deprotonation. 

There are indications that smooth deacylations, known for 1-acylaziridines, are also encountered in diaziridine chemistry. The two benzoyl groups in (130) can be removed... 

Me2CHCH2)2AlH, PhCH3, —78°, 80% yield. Since the /V-benzoyl group in this substrate could not be removed by hydrolysis, a less selective reductive cleavage with diisobutylaluminum hydride was used. 

First the five protons (integral) of the //NMR spectrum (Sfj = 7.50 - 7.94) in the chemical shift range appropriate for aromatics indicate a monosubstituted benzene ring with typical coupling constants 8.0 Hz for ortho protons, 1.5 Hz for meta protons.). The chemical shift values especially for the protons which are positioned ortho to the substituent Sn = 7.94) reflect a -M effect. Using the CH COLOC plot it can be established from the correlation signal hclS = 66.AI7.94 that it is a benzoyl group A. 

Phenacylpyridinium bromide (155) with aqueous sodium carbonate yields the chloroform soluble zwitterion (156) which, with dimethyl acetylenedicarboxylate in the presence of palladium on charcoal, cyclized to the indolizine (157) in ca. 20% yield. In a similar way the pyrazine (158) gave a mixture of (159) and (160) through loss of the benzoyl group. The last compound was also ob-... 

Azauridine was also synthesized using the knowledge of the course of alkylation of 6-azauracil 2-methylmercapto derivatives (e.g., Section II,B,4,b). The 1-ribofuranosyl derivative obtained by reaction of the mercury salt of the 2-methylmercapto derivative with tri-O-benzoyl-jS-D-ribofuranosyl chloride on removal of the methyl-mercapto and then benzoyl groups yielded crystalline 6-azauridine, The main difference between uracil and 6-azauracil nucleosides consists in the preparation of cyclic nucleosides. It is known that uridine can be readily converted to cyclic nucleosides by the reaction of 2 (50-O-mesyl derivatives with nucleophilic agents, Analogous... 

On mild heating of its ethanolic solution, rearrangement occurs with the shift of a benzoyl group. The structure of the cyclohexanone... 

Relatively few pyridines with substituents other than alkyl groups have so far been examined, and with some of these the reaction has been carried out only in the presence of added solvent. A comparison of the reactivities of these pyridines is therefore difficult. It has, however, been established that the presence of benzoyl groups in the 3- and 4-positions causes a very marked drop in the yields of the corresponding 2,2 -bipyridines. The 3- and 4-benzylpyridines were found to be more reactive but even in the absence of solvent, and in vacuo, 4-benzylpyridine gave only about one-third of the yield of the 2,2 -bipyridine compared with pyridine itself. Ethyl nicotinate in the absence of solvent and under vacuum -- gave a similar yield of biaryl but 4-phenylpyridine was found to be less reactive. 

Replacement of chlorine on the pendant benzoyl group by azide is apparently consistent with antiinflammatory activity. Acylation of indomethacin intermediate with p-nitrobenzoyl chloride leads to the corresponding amide (7). Saponification ( ) followed by reduction of the nitro group gives the amine 9. The diazonium salt (10) obtained on treatment with nitrous acid is then reacted with sodium azide there is thus obtained zidomethacin (11). 

To support a polystyrene onto the upper rim of ca-lix[4]arene (phenolic-O- of calix[4]arene) and 25,26,27-tribenzoyloxy-28-hydroxy, calix[4]arene was treated with chloromethylated polystyrene in the presence of K2CO3 (Scheme 7). Polymeric calix[4]arene (3a) thus obtained was hydrolyzed in the benzoyl groups prior to use for the extraction process. 

The polymeric calixarene(2) thus obtained was hydrolyzed with ethanolic NaOH solution to remove the benzoyl groups prior to use for the extraction process. 

To investigate whether these results were caused by the oligomer (7) or calix[4]arene itself, experiments were performed with calix[4]arene, before it was reacted with 7. Observations showed that when extraction was performed with unreacted calix[4]arene, the transfer of Ag", Hg", and Hg " ions was very close to unity. The compound (8) contains benzoyl groups. To understand the effect of this group on the extraction process, the... 

When it s necessary to refer to the R-C=0 as a substituent, the name acyl (a-sil) group is used and the name ending -yl is attached. Thus, CFI3CO is an acetyl group, CHO is a formyl group, and C6H5CO is a benzoyl group. 

Benzophenone, structure of, 697 Benzoquinone, electrostatic potential map of, 631 Benzoyl group, 697 Benzoyl peroxide, ethylene... 

Highly substituted dimethyl 2,4-diphenyl-3-benzoxepin-l,5-dicarboxylate was converted by irradiation to an indene derivative 4 which had lost one benzoyl group by acidic hydrolysis.146... 

The 1-benzoyl-l//-l,2-diazepines 3 undergo loss of the A -benzoyl group and ring contraction to provide the pyridines 4 in refluxing xylene (see Houben-Weyl, Vol. E7b, p 519).93... 

In the Mukaiyama variation of the aldol reaction, 3-benzoyloxy-2-trimethylsiloxy-l-butene adds to 2-methylpropanal in a stereoselective manner. Best results are obtained in the presence of titanium(IV) chloride, giving the adducts 9/10 in a diastereomeric ratio of 92 8. Hydrolysis of the benzoyl group and subsequent oxidative cleavage of the 1,2-diol moiety liberates / -hy-droxycarboxylic acids593. 

Carbonyl groups on the side chains also activate the dihalides. These particular dihalides were employed to prepare polyfarylenc ether)s containing pendent benzoyl groups.82 The polymers may be used as a positive photoresist for UV irradiation. 

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