The investigation in 2,3'-biquinoline series 26.* Regioselective nitration of 1'-alkyl-1',4'-dihydro-2,3'-biquinolin-4'-ones and 1'-alkyl-1',2'-dihydro-2,3'-biquinolin-2'-ones

The nitration of 1'-alkyl-1',4'-dihydro-2,3'-biquinolin-4'-ones and 1'-alkyl-1',2'-dihydro-2,3'-biquinolin-2'-ones has been investigated. It was shown that the regioselectivity of nitration of the first depends on the acidity of the medium and the order of adding reactants. In strongly acidic medium 1'-alkyl-5,6'-dinitro-1',4'-dihydro-2,3'-biquinolin-4'-ones or mixtures of them with 1'-alkyl-5-nitro-1',4'-dihydro-2,3'-biquinolin-4'-ones are formed. In less acidic media 1'-alkyl-6'-nitro-1',4'-dihydro-2,3'-biquinolin-4'-ones and then 1'-alkyl-6,6'-dinitro-1',4'-dihydro-2,3'-biquinolin-4'-ones are formed. Nitration of 1'-alkyl-1',2'-dihydro-2,3'-biquinolin-2'-ones leads to 1'-alkyl-6'-nitro-1',2'-dihydro-2,3'-biquinolin-2'-one and then 1'-alkyl-6,6',8'-trinitro-1',2'-dihydro-2,3'-biquinolin-2'-one. *For Communication 25 see [1]. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 578-585, April, 2009.     

2,3-Benzodiazepine-1-thione in the synthesis of substituted and hetero-annelated 2,3-benzodiazepines

A series of S-substituted and 1,2-annelated derivatives of 2,3-benzodiazepine has been obtained on the basis of 2,3-benzodiazepine-1-thione. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, 594-601, April, 2009.     

Investigations In the Field of 2,3'-Biquinolyl. 13. Regioselectivity in the Nitration of 2,3'-Biquinolyls and Their 1',4'-Dihydro Derivatives

The nitration of 2,3'-biquinolyls in concentrated sulfuric acid with an equivalent amount of nitric acid at room temperature takes place exclusively at the 2-quinolyl fragment with the formation of the 5- and 8-nitro derivatives or their mixtures. The nitration of the 1',4'-dihydro derivatives under these conditions leads to analogous compounds. Reduction of the nitrobiquinolyls gives the respective amines. Acylation of the latter leads to acylamino-2,3'-biquinolyls.     

Investigations on 2,3'-Biquinolyls. 15. Regioselectivity of the Addition of Nitromethane Anion to 1'-Alkyl-3'-(2-quinolyl)quinolinium Halides

1'-R-3'-(2-Quinolyl)quinolinium halides react with nitromethane forming products of addition at the position 4', the 1'-R-4'-nitromethyl-1',4'-dihydro-2,3'-biquinolyls. A method has been developed for the synthesis of 1'-phenacyl-1',4'-dihydro-2,3'-biquinolyls based on the alkylation of 1',4'-dihydro-2,3'-biquinolyl with halogen derivatives in DMF.     

Investigations in the Field of 2,3'-Biquinolyl. 14. Reaction of Dihydro Derivatives of 2,3'-Biquinolyl with Bromine and Iodine

Methods were developed for the synthesis of 6'-bromo- and 6',8'-dibromo-2,3'-biquinolyls and 3',4'-dibromo- and 3',4',6'-tribromo-1'-ethoxycarbonyl-1',2',3',4'-tetrahydro-2,3'-biquinolyls on the basis of the bromination of the dihydro derivatives of 2,3'-biquinolyl. It was shown that the reaction of 1'-alkyl-1',4'-dihydro-2,3'-biquinolyls with bromine and iodine leads to 1'-alkyl-1',2'-dihydro-2,3'-biquinolyl-2'-ones.     

DIE KINETIK DER REAKTION VON 2-PROPYLCHLORFORMIAT MIT ALKALIRHODANIDEN II. DER REAKTIONSWEG ZUR BILDUNG DES 2-PROPOXYCARBONYLISOTHIOCYANATS

Abstract

By rate determination between 26°C and 54°C the formation of 2-propyloxycarbonylisothiocyanate is shown to occur in a reaction sequence via the intermediate 2-propyloxycarbonylthiocyanate.

Durch die Bestimmung der Reaktionsgeschwindigkeit im Temperaturbereich zwischen 26°C und 54°C wird gezeigt, daβ die Reaktion zur Bildung von 2-Propoxycarbonylisothiocyanat überwiegend als Reaktionsfolge über das Zwischenprodukt 2-Propoxycarbonylthiocyanat verläuft.     

Quinoxaline-2,3(1H,4H)-dithione: Synthesis and reactions

Quinoxaline-2,3(1H,4H)-dithione can be synthesized efficiently through the thionation of quinoxaline-2,3(1H,4H)-dione with phosphorous pentasulfide. It can also be obtained by reaction of 2,3-dichloroquinoxaline with thiourea or sodium hydrogen sulfide. The most common reactions of quinoxaline-2,3(1H,4H)-dithione involve deprotonation and electrophilic attack at the sulfur atoms to give various substituted derivatives and poly-fused heterocyclic ring systems. The current review aims to provide a survey of the developments in quinoxaline-2,3(1H,4H)-dithione chemistry until 2016.     

Highly efficient synthesis of 2,3-dihydroquinazolin-4(1H)-ones catalyzed by heteropoly acids in water

<正>Heteropoly acids efficiently catalyzed the cyclocondensation reaction of anthranilamide with aldehydes in water at ambient temperature and afforded the corresponding 2,3-dihydro-4(1H)-quinazolinones compounds in good to excellent yields.This method provides mild reaction conditions and clean reaction profiles,using a small quantity of catalyst and a simple workup procedure.     

COPPER-CATALYSED REARRANGEMENT OF 4-SUBSTITUTED-2,3-1H-BENZOXAZINE-1-THIONES

Abstract

4-Substituted-2,3-1H-benzoxazine-1-thiones were prepared by the treatment of the corresponding benzoxazine-1-ones with P₂S₅. The thermal rearrangement of 4-substituted-2.3-1H-benzoxazine-1-thiones, catalysed by metallic copper, yielded 4-substituted-2.3-1 H-benzthiazine-1-ones.     

Investigation of 2,3'-Biquinolyl. 10. The Regioselectivity of the Reaction of 2,3'-Biquinolyl and 1'-Alkyl-3-(2-quinolyl)quinolinium Halides with Halo Derivatives in the Presence of Metallic Lithium and Magnesium

2,3'-Biquinolyl reacts with halo derivatives in the presence of metallic lithium to give addition products at position 4', treatment of which with water gives 4'-R-1',4'-dihydro-2,3'-biquinolyls and with halo derivatives gives 1'-alkyl-4'-R-1',4'-dihydro-2,3'-biquinolyls. The reaction of 2,3'-biquinolyl with halo derivatives in the presence of metallic magnesium gives a mixture of products of addition at positions 2' and 4'. 1-Alkyl-3-(2-quinolyl)quinolinium halides and halo derivatives with metallic magnesium give 1'-alkyl-2'-R-1',2'-dihydro-2,3'-biquinolyls but form a complex mixture of substances when metallic lithium is used.     

Synthesis of Phenyl-2,3-oxazine Derivatives of Chrysenequinonecarboxylic Acid

A mixture of isomeric phenyloxazines (2, 3) in a 5:4 ratio was synthesized via a [4 + 2] addition reaction of a heterocyclic diene-precursor prepared from bromoacetophenone oxime and the methyl ester of chrysenequinonecarboxylic acid (1). The structures of the synthesized compounds were confirmed using spectral methods.     

Synthesis of 2‐Aryl‐2,3‐dihydro‐1,8‐naphthyridin‐4(1H)‐ones by Deprotective Cyclization of N‐{3‐[(2E)‐3‐Arylprop‐2‐enoyl]pyridin‐2‐yl}‐2,2‐dimethylpropanamides in Water

A new and convenient method for the preparation of 2‐aryl‐2,3‐dihydro‐1,8‐naphthyridin‐4(1H)‐ones 4 has been developed. Thus, N‐{3‐[(2E)‐3‐arylprop‐2‐enoyl]pyridin‐2‐yl}‐2,2‐dimethylpropanamides 3 are synthesized from commercially available pyridin‐2‐amine using an easily performed three‐step sequence and are subjected to cyclization with deprotection under acidic conditions in H₂O to give the desired products. Similarly, 2‐aryl‐2,3‐dihydro‐1,7‐naphthyridin‐4(1H)‐ones 8 and 2‐aryl‐2,3‐dihydro‐1,6‐naphthyridin‐4(1H)‐ones 12 can be prepared from pyridin‐3‐amine and pyridin‐4‐amine, respectively.     

新型3-氟苯基-1H-咪唑基甲胺基衍生物的合成

以4-咪唑甲醛为原料,通过保护、格氏反应、酰化、取代、脱甲基或甲酯共5步反应合成了4种新型的3-氟苯基-1H-咪唑基甲胺基衍生物,5步总收率分别为21%、18%、22%和24%,终产物结构经1H NMR、13C NMR和HR-MS(ESI)确证。     

A facile synthesis of 2-substituted-2,3-dihydro-4(1H)-quinazolinones in 2,2,2-trifluoroethanol

2-Substituted-2,3-dihydro-4(1H)-quinazolinones were obtained in high yields by condensation of anthranilamide with aryl, alkyl or heteroaryl aldehydes or ketones in the refluxing 2,2,2-trifluoroethanol without any catalyst.     

Oxalylation of the 3-oxo-<Emphasis Type="Italic">N</Emphasis>-phenyl-3-R-propanethioamides

Oxalylation of 3-oxo-N-phenyl-3-R-propanethioamides in aprotic solvents in the temperature range from −40°C to +20°C results in 4-acyl-5-phenylamino-2,3-dihydrothiophene-2,3-diones and 2-(2-oxo-2-R-ethylidene)-3-phenyl-1,3-thiazolidine-4,5-diones, while in the presence of potassium carbonate, potassium 4-acyl-2,3-dioxo-1-phenyl-2,3-dihydro-1H-pyrrole-5-thiolates are formed.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 757-760, March, 2005.