Pyridine, 4-benzoyl 4-chloro

Thermolysis of the 3-acyl-3/f-azepine 32 in Decalin at 250°C also gives the phenacylpyridine but in much reduced yield (6%). In a similar manner, 4-chloro-yV,/V-diethyl-3-phenacylpyridin-2-amine (53 % bp 160 C/0.18 Torr) is produced by the photolysis or thermolysis of 3-benzoyl-5-chloro-Ar,Ar-diethyl-3/f-azepin-2-amine.246 However, if the 3ff-azepine bears a secondary amine residue at the 2-position, e.g. 36, then photolysis or thermolysis yields a pyrrolo[2,3-/>]pyridine by intramolecular cyclization of the 3-phenacylpyridin-2-amine intermediate. 

In general, reactive carbon electrophiles have been shown to react preferentially at the nitrogen atoms of the purine bicycle (see Section 10.11.5.2.1). However, 9-(2,3,5-tris-0-/r /T-butyldimethylsilyl)-a-D-ribofuranosyl-6-chloro-2-(tri-butylstannyOpurine reacted with benzoyl chloride to substitute the 2-tributylstannyl group (PhCOCl, pyridine, toluene, 60% yield) <1997JOC6833>. Indirect C-alkylations have been achieved through deprotonation and alkylation see Section 10.11.5.3.4. The major routes to (7-alkyl and (7-aryl substitution are through nucleophilic displacement or transition metal-catalyzed reactions of halopurines see Sections 10.11.7.4.1 and 10.11.7.4.2. 

The acylation of a series of pyrazolo[3,4-c]pyridines has been studied.110 Acetic anhydride in refluxing benzene converted S-substituted derivatives to 1-acyl compounds (101 R2 = H), whereas the 7-methoxy derivative afforded the 2-substituted product 102 (R1 = H, R2 = OMe), attributed to peri interaction. In the absence of solvent, however, the latter reaction gave the 1-acyl isomer as the major product. Furthermore, benzoylation of the 5-chloro bicycle furnished a mixture of 101 and 102 (R1 = Cl, R2 = H). However, products benzoylated mainly at N-6 were obtained following introduction of a nitro group into the pyrazole ring. 

Thorpe-Ziegler synthesis of 3-aminoindoles with additional functional groups was used as part of the synthesis of condensed indoles [e.g., azepines (94) were obtained from 3-amino-2-benzoylindoles (93) (91JHC379) (Scheme 24)]. In these cases the nature of the substituent R is important for a smooth reaction (Ac < Bz < 2-N02-benzoyl, but no reaction when R = H). With 2-chloro-3-(/V-bromoacetyl-/V-methylamino)pyridine and o-benzoylaminobenzonitriles (95), the condensed pyridodiazepinones 97 and 99 (95H753) were obtained via intermediates 96 and 3-aminoindoles intermediate (via 98) 3-aminoindoles followed by substitution of the 2-chloro substituent by the resulting 3-amino group (Scheme 25). 

Pyrazolo[3,4-Z)]pyridines, the 7-chloro-6-fluoro-2,4-dimethylquinoline and its mercapto-thiadiazolyl or oxadiazolyl quinolines 21 were prepared via Diels-Alder reaction conversion of methyl 2-(3-oxo-3-phenylpropenylamino)benzoate into 3-benzoyl-l.S -quinolin-4-one 22 . A mixture of aniline derivatives and malonic ester gave a variety of 3-aryl-4-hydroxyquinolin-2(l//)-ones 23. Condensation of isatins with ketones afforded quinoline-4-carboxylic acids. 2-Aryl-l,2,3,4-tetrahydro-4-quinolinones 22 and carbazolylquinolone were also prepared. The substitution of 2-chloroquinoline gave the 2-substituted quinolines. Basic alumina has catalyzed the C-C bond formation between 2-hydroxy-1,4-naphthoquinone and 2-chloroquinoline derivative to give 21. Reaction of organic halides with 8-hydroxyquinolines gave the respective ethers. The azodye derivatives of 21 were prepared in the absence of solvent. Silica gel catalyzed the formation of 2-ketomethylquinolines from reaction of 2-methylquinolines with acyl chlorides. 

Acetyl or benzoyl chloride and 2-picoline-1-oxide in nonaqueous solvents give the acetate or benzoate of 2-pyridinemethanol and a small amount of 2-pyridylmethyl chloride " Pyridine-1 -oxide and tosyl chloride in benzene give 2,3-dipyridyl ether, AT-(2 -pyridyl)-2-pyridone, A -<2 -pyridyl)-5-chloro-2-pyri-done, A (2 -pyridyl)-3-chloro-2-pyridone, and 3-tosyloxypyridine. Tracer studies have suggested that the 3-tosyloxypyridine is formed via an intimate ion pair (xn-443). (For alternate suggestion, see Ch. I). 

The 1-deazauridine (XU-587) has been prepared from 3-bromo-2,6-di-benzyloxypyridine by means of conversion to the 3-pyridyllithium and then to the di-3-pyridylcadmium (XU-584). Treatment of XII-584 with l-chloro-2,3,5-tri- -benzoyl-/3-D-ribofuranose gives a 2,6-dibenzyloxy-3-(D-ribofuranosyl)-pyridine (MI-585) and the benzylidene derivative (MI-586). Hydrogenolysis of XII-585 gives a 3-ribosyl-2,6-dihydroxypyridine (XII-587). 

Chloro-2-ethyl-l,2-benzisothiazolium chloride in abs. pyridine treated with acetophenone, stirred and heated 0.5 hr. at 100° 2-benzoyl-3-ethylamino-thianaphthene. Y 60-80%. F. e. s. H. Boshagen and W. Geiger, A. 764, 58 (1972). 

Ethoxy-, -chloro- and -phenoxy-pyridine 1-oxides give 2-hydroxypyridine 1-oxide, the oxide function surviving in these cases" . An unusual example is that of 2-carboxy-5-methoxycarbonylpyridine 1-oxide. With benzoyl chloride in dioxan this gives 6-hydroxynicotinic acid. However, with acetic anhydride or acetyl chloride, methyl 4-acetoxynicotinate results . 

Functionally substituted (77 -cyclopentadienyl)dicarbonyl iridium compounds were prepared from reactions of the corresponding substituted cyclopentadienyl-Na, -Li, or -T1 reagents with chlorodicarbonyl(pyridine)iridium. Ring-substituted compounds include chloro, benzyl, acetyl, carbomethoxy, methyl, benzoyl, trimethylsilyl, cyano, dimethylamino, tetra-Ph, dimethylaminoethyl, (tetramethyl)dimethylaminoethyl, methoxyethyl, pcntabenzyl, and pentamethyl. The symmmetric and antisymmetric carbonyl stretching frequencies as well as the NMR chemical shifts of the carbonyl substituents were correlated with various Hammett substituent parameters. ... 

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