Synthesis of Some Heterocyclic Compounds Via Cyclization of Imidoyl Chloride

ا ةصلاخل ض م ممم ض ممم زا ضاممم ضضضممم ضم ممم رتضحمممت (ضا ز a-e ) 3 ض ض ممم ض ممم ت ضزممما من ضيممما ل ضاممم (ضضممم مزانض زضممم ض ممم زا a-e ) 2 ض ض ممم زا ضيممما ل ضاممم ض عم ممم رتضحمممتضممممت ( N ض ض ممم ف (ضضمم مض ع a-e ) 1 ض ض ز مم ضمممفضا زمضمم ي ضضمم زانض مم ضم م كمم زض)مزلمم ل ضضمم زانضممم اض مم ضيمم ز ض م ض ممي فضض م ضيم ز ض مم زرتضحمتضتماط ضمممفض م نضيمما ة ضضم زانزمض عضا ضم ض مممم نم ض ( a-e ) 4 ض ضامممم ض ممممنض مممم ض مممميتة زرضحممممتضمممممت 1 , 2 , 3 ض ض زمممما ض ز مممم مت ضض ض ( a-e ) 5 ض ض مممم ز


Introduction
Imidoylations of organic compounds enable the preparation of wide variety of compounds classes.Thus, imidoylation at nitrogen are used for the preparation of amidines, guanidines, and N-substituted derivatives (1) .Imidoyl chloride could be prepared by several methods the imidoyl chloride can be prepared by treatment of the corresponding amides with phosgene, oxalyl chloride.
Or phosphorous penta chloride ( ² ) chlorination of tertiary amines and of the acyl derivatives of primary and secondary amines at high temperature (~ 200º) gives imidoyl chloride ( ³ ) and chlorination of isothyocyanates, thioamides give these (4,5) .The most popular method is the reaction of anilide and phosphorus penta chloride which was first investigated by Sohn, Muller and Mosetting (6,7) .Among the reactions of imidoyl is the elimination of hydrogen halide from N-Benzyl halides giving the corresponding nitratile yields; some cycloaddition reactions of this system lead to the formation of compounds such as pyrrole, iminazole and oxazole series (8) .Derivatives of pyrazoles and 1, 2, 3 triazole pharmacotherapy gave displayed abroad spectrum of biological activities, anti-inflammatory, anti-fungal, anti-arrhythmic, tranquilizing, muscle relaxing, psycho analeptic, anticonvulsant, mono amine oxidase inhibiting, anti-diabetic and anti bacterial activities (9) .Chemotherapeutic importance of imidazole derivatives is well recognized, some 5substituted triazeno imidazole-4-carboxamides has been founded to have potential anti cancer agents (10) .The effectiveness of condensed heterocyclic containing pyridine, pyrmidine, thiazole, imidazole rings acts as anti depressants (11) and anti hermitic agents (12) .Dihydro Folate and imidazole derivatives such as metronidazole, secnidazole (13) , the classes of compounds belong to the hydroxyl and alkoxy containing imidazole class were found to have anti fungal properties (14,15) .
Pyrazole and benzamidazole ring have drawn much considerable, interest and were found to be used as a source of endless research both in nature (such as amino acid, histidine, vitamin B12, component of DNA base structure and purines, histamine, biotin) this finding obviously important in pharmaceutical investigation (16,17) .Iminazoles formed from certain unstable bisimidoyl halides based on oxalis acid (18) and quinolines are produced by self-condensation of certain N-aryl imidoyl halides (19) .
Synthesis of (substituted-N-phenyl amino imidoyl chloride) 2(a-e) (21) Compounds 1(a-e) (0.05 mole) and phosphorous penta chloride (0.05 mole) in 25 ml of dry ether and refluxed for 24 hrs under anhydrous condition.After the reaction has been completed it was cooled and a solution of (15gm) of phenol in (25ml) of dry ether and methanol (40ml) was then added.The solvent was evaporator to halve its volume.The final mixture was left in cool box 5 days.theproduct was separated as prisms crystals.

(a-e)
A mixture of (0.01 mole) of compounds 3(a-e) was dissolved in (40 ml) of dry chloroform and (0.1 mole) of absolute ethanol.The mixture was saturated with hydrogen chloride gas with cooling at 0º C flask is Stoppard and place in refrigerator for 7 days and then equal volume of dry ether added.The imidate hydrochloride filtered off and directly in further step. (23)

Synthesis of 2-(1-phenyl -3-substituted -2-pyrazoline -5-yl) -1, 3imidazoline (22) 7 (d,e)
A mixture of (0.01 mole) of compounds 4 (d,e) and (0.6gm, 0.01 mole) of ethylene diamine in 15 ml of absolute ethanol.The mixture was refluxed for 6 hrs.Then kept at 0ºC overnight.The small amount of salt was filtered off.The filtrate then was evaporated and the residual recrystallized from water.The melting point IR data and % yield of the synthesis of compounds were showed in table (1).

Results and Discussion:
As it was mentioned in the introduction there were different methods for the preparation of imidoyle chloride among which is the conversion of the corresponding phenyl hydrazide using PCl 5 as chlorinating agent.Scheme (1) shows this transformation into compounds 2(a-e) which was characterized by the main absorption bands as indicated in table (1) compounds 2(a-e) was cycled by acrelonitrile into pyrazoline derivatives 3(a-e) this compounds were characterized by stretching band (C≡N) at (2118-2358).Compounds 4(a-e) were obtained as amidine hydrochloride upon treatment of compounds 3(a-e) with HCl absolute ethanol.these compounds were characterized by stretching bands (C=N) absorbed at (1618-1646) cm -1 , (C-O) band absorbed within the rang at (1036-1116) cm -1 , and (N-H) band absorbed at (3241-3449) cm -1 .