4-Azido-8- quinoline

Alkoxypyridoazepines, e.g. 34, behave in a similar manner to yield pyridoazepinamines, e g. 35, which, in many cases, are not obtainable directly by photolysis of the appropriate azido-quinoline or azidoisoquinoline in amine solution108 151 (see Section 3.2.1.4.1.5.). 

Interest in the Staudinger reaction of phosphines with azides, and the Mit-sunobu reaction involving nucleophilic attack by phosphorus at nitrogen in esters of diazodicarboxylic acids, has continued. Systems of the type (205) have been obtained from the reactions of secondary arylphosphines with azides. Treatment of these with butyllithium results in deprotonation to form the diaminophosphonium diazaylides (206). Phosphazenes have been prepared from azido-quinolines and -triazines, and also from diazoketones " and polycyanocyclopropanes. The Staudinger reaction has been employed in the synthesis of phosphorus-containing dendrimers, and in new approaches to amide and peptide synthesis. The reaction has also been used in a high-... 

Following a similar approach, triazole 13 with an aryl substituent at position 5 can be prepared from 4-azido-quinoline and 3-oxo-3-phenyl propionic acid. This compound strongly inhibited specific binding of diazepam to its target [15]. 

Intermolecular addition of photochemically generated nitrenes and in particular acylnitrenes to alkenes provides a useful and widely applied route to aziridines.385 An analogous intramolecular photoreaction is thought to be involved in the conversion of the o-azidophenylethylfuran 461 into the pyrrolo[l,2-a]quinoline 462 as outlined in Scheme 13,386 and intramolecular addition to an azo group has been observed in the 8-azido-1-arylazonaphthalenes 463.387... 

Smalley et al. reported the synthesis of the cyano-containing keto ester 98 by reaction of o-azidobenzoyl chloride 97 with cyanoacetic ester in the presence of triethylamine. This keto ester was then heated in acetonitrile for 30 min and gave the ring closed product 99 which was isolated in the fully aromatic tautomeric form 100 <1997S773>. A similar approach to tetrazolo[l,5- ]quinolines has been applied by a Korean research group in this case a reflux of the cyano-azido compound 101 for a longer period was needed in order to accomplish the cyclization to 4-acetoxymethyl-tetrazolo[l,5- ]quinoline 102 <2003JHC1103>. 

Another approach to the syntheses of quinazolines involves 3-(o-azido-phenyl)isoxazoles (210) which are accessible from a-chloro-Z-azido benzal-doximes (209) and /3-keto esters (R = Ph, = OEt). As shown in Scheme 78, the iminophosphorane resulting from the Staudinger reaction is transformed without isolation by an aza-Wittig reaction into 3,4-disubstituted isoxazolo[4,3-c]quinolines (211) (92MI1). 

Stadlbauer, W. et al, J. Chem. Soc., Perk. I, 2000, (18), 3085 A literature preparation of this compound by diazotisation of 3-amino-4-hydrazino-l//-pyrazolo[3,4-b]quinoline was found to give the still more energetic isomer 4-azido-3-diazo-3//-pyrazolo[3,4-b]quinoline. 

A-Azidocarbonylazepine, 2724 Azidocarbonylguanidine, 0816 4-Azidocarbonyl-1,2,3-thiadiazole, 1066 4-Azido-3-diazo-3//-pyrazolo[3,4-b]quinoline, 3231b 2-trans-1 -Azido-1,2-di hydroacenaphthyl nitrate, 3460 /V-Azidodimethylamine, 0911... 

Azine approach. Thermal reactions between the vicinal nitro-azido groups in the pyridine (643) (7lJCS(C)l2i l) and in the quinoline (644) (68JCS(B)1516) yield the fused furoxanes. 

Intramolecular carbenoid and nitrenoid insertions are also quite effective for the preparation of peri-condensed heterocycles. Thus, photolysis of 1-naphthyl-1,2,3-triazoles 113 leads to bcnzo[d,e quinolines 115, possibly via carbene intermediate 114 (Scheme 55) <1987J(P1)413>. Similarly, on photolysis or thermolysis of 8-azido-l-arylazonaphtha-lenes 116 naphtho[l,8-<7, ]triazine derivatives 117 are formed along with A-aryhminobenzo[/y/]indazoles 118 (Scheme 56) <1978JOC2508, 1982JOC1996>. 

Azido amino quinoline,and Diazido amino quinoline, — not found in Beil... 

Many ring-fused imidazole derivatives have been synthesized by various methods. Domino Michael addition retro-ene reaction of 2-alkoxyiminoimidazolidines and acetylene carboxylates provided a synthesis of 2,3-dihydroimidazo[l,2-a]pyrimidin-5-(l//)-ones <05T5303>. A single step synthesis of 3,5-dialkyl-9-nitroimidazo[l,2-c]quinazolin-2(3//)-ones from simple carbonyl compounds, primary amines or amino acid methyl esters and 2-azido-5-nitrobenzonitrile has been published <05TL5778>. Diels-Alder reaction of azadienes and benzimidazole-4,7-diones afforded imidazo[4,5-g ]quinoline-4,9-dione derivatives <05EJ01903>. Reaction between isocyanides and dialkyl acetylenedicarboxylates in the presence of 4,5-diphenyl-l,3-dihydro-2//-imidazol-2-one provided a one-pot synthesis of 5//-imidazo[2,l-ft][l,3]oxazine derivatives <05T2645>. Microwave irradiation was employed in the synthesis of 1-ary 1-3-acetyl-1,4,5,6-... 

Hydrazino-l-methylquinolinium fiuoroborate in acetonitrile mixed at 0° with a soln. of ca. 2 moles 2-azido-3-methyl-6-methoxybenzothiazolium fiuoroborate in the same solvent, then 3 moles pyridine added dropwise with stirring, and the product isolated after 20 min. (3-methyl-6-methoxy-2-benzothiazole)(l-methyl-2-quinoline)pentaazapentamethinecyamne fiuoroborate. Y 76%. F. e. s. S. Hiinig and H. Quast, A. 711, 139 (1968). 

The [Ru(bpy)3] photocatalyst was also applied in the following novel visible-light driven processes (i) synthesis of indazolo[2,3-a]quinoline derivatives from 2-(2-nitrophenyl)-l,2,3,4-tetra-hydroquinolines (ii) azido- and amino-trifluoromethylation of alkenes (iii) reduction of nitro compounds to oximes (iv) generation of aryl radicals by visible-light photocatalytic reduction of sulfonium salts. ... 

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