1. Microwave assisted synthesis of sydnonyl- substituted imidazoles

2. A one-pot condensation of 3-aryl-4-formylsydnones, 1,2-diketones, and ammonium acetate in the presence of acetic acid by classical heating at 90-110 o C for 1-3 days afforded a diverse array of 4,5- diaryl-2-sydnonyl substituted imidazoles. Such reaction could be completed successfully within several minutes with a microwave irradiation. 1a: Ar = C 6 H 5 ; 1b: Ar = p-CH 3 C 6 H 4 ; 1c: Ar = p-CH 3 OC 6 H 4 ; 1d: Ar = p-C 2 H 5 OC 6 H 4 2a: Ar' = C 6 H 5 ; 2b: Ar' = p-CH 3 OC 6 H 4 ; 2c: Ar' = p-FC 6 H 4 ; 2d: Ar' = 2-thienyl

3. Multiwave 3000 was designed by Anton Paar Gmbh. It includes various rotors for fast and complete closed vessel digestion of organic or inorganic samples under high pressure and temperatures.

4. power: 200w (100w/each ); ramp: 1min pressure: 35 bar; 0.5 bar/sec temperature: 90 o C; hold: 30min

5. Table 1. Comparision between microwave irradiation (M.W.) and conventional heating in the syntheses of imidazoles 3a-6d Starting materials1,2-DiketonesProductsC. H. Reaction Time C. H. Yield * (%) M. W. (100W) Reaction Time M. W. (100W) Yield * (%) 1a ( Ar = C 6 H 5 )2a3a1.5 days4645 min52 1b ( Ar = p-CH 3 C 6 H 4 )2a3b1.5 days6145 min78 1c ( Ar = p-CH 3 OC 6 H 4 )2a3c1.5 days5145 min69 1d ( Ar = p-C 2 H 5 OC 6 H 4 )2a3d1.5 days7545 min76 1a ( Ar = C 6 H 5 )2b4a2 days5845 min70 1b ( Ar = p-CH 3 C 6 H 4 )2b4b2 days7745 min80 1c ( Ar = p-CH 3 OC 6 H 4 )2b4c2 days6445 min74 1d ( Ar = p-C 2 H 5 OC 6 H 4 )2b4d2 days6745 min75 1a ( Ar = C 6 H 5 )2c5a2 days5960 min78 1b ( Ar = p-CH 3 C 6 H 4 )2c5b2 days7260 min85 1c ( Ar = p-CH 3 OC 6 H 4 )2c5c2 days6060 min76 1d ( Ar = p-C 2 H 5 OC 6 H 4 )2c5d2 days6560 min80 1a ( Ar = C 6 H 5 )2d6a3 days5790 min65 1b ( Ar = p-CH 3 C 6 H 4 )2d6b3 days5290 min62 1c ( Ar = p-CH 3 OC 6 H 4 )2d6c3 days5290 min60 1d ( Ar = p-C 2 H 5 OC 6 H 4 )2d6d3 days4890 min58

6. 4,5-Diaryl-2-sydnonyl-1- substituted imidazoles could also be prepared by one pot condensation of 3-aryl-4-formylsydnones, benzil derivatives, ammonium acetate and 1 o amines by the similar treatment. 1d: Ar = p-C 2 H 5 OC 6 H 4 ; 2a: Ar' = C 6 H 5 ; 2b: Ar' = p-CH 3 OC 6 H 4 ; 2c: Ar' = p-FC 6 H 4 7a: R' = iso-butyl; 7b: R' = C 6 H 5 CH 2 CH 2 ; 7c: R' = C 6 H 5 CH 2 ; 7d: R' = CH 3 (CH 2 ) 5

7. Table 2. Comparision between microwave irradiation (M.W.) and conventional heating in the syntheses of imidazoles (8a-10a) 1,2-DiketonesAminesProductsC. H. Reaction Time C. H. Yield * (%) M. W. (100W) Reaction Time M. W. (100W) Yield * (%) 2a7a (R' = iso-butyl)8a3 days343 hr56 2a7b (R' = C 6 H 5 CH 2 CH 2 )8b2 days252 hr47 2a7c (R' = C 6 H 5 CH 2 )8c2 days202 hr46 2a7d (R' = CH 3 (CH 2 ) 5 )8d2 days222 hr50 2b7a (R' = iso-butyl)9a3 days203 hr45 2b7b (R' = C 6 H 5 CH 2 CH 2 )9b2 days342 hr60 2b7c (R' = C 6 H 5 CH 2 )9c2 days262 hr55 2c7a (R' = iso-butyl)10a3 days283 hr56

8. Figure 1. ORTEP drawing of compound 3-(4-ethoxyphenyl)-4- (1- isobutyl-4,5-diphenyl-1H-imidazol-2-yl)sydnone (8a).

9. Figure 2. ORTEP drawing of compound 3-(4-ethoxyphenyl) -4-(1- phenethyl-4,5-diphenyl-1H-imidazol-2-yl)sydnone (8b).

10. Figure 3. ORTEP drawing of compound 4-(1-benzyl-4,5-diphenyl – 1H-imidazol-2-yl)-3-(4-ethoxyphenyl)sydnone (8c).

11. Figure 4. ORTEP drawing of compound 4-[4,5-Bis-(4-fluorophenyl)-1- isobutyl-1H-imidazol-2-yl]-3-(4-ethoxyphenyl)sydnone (10a).