Table 13: 13C NMR Data for 5a-e; chemical shifts in ppm relative to TMS(1%) at room temperature in CDCl3.

        Piperazine      
No. X Aromatic Piperazine I II CH2 CH3 X
5a p-CN 153.9,137.6,135.8, 52.2(br) (a) 60.7 19.3 108.4(CN)
133.1, 130.5
    129.9,127.5,125.7,          
    121.2, 119.5          
    154.2,137.6,135.9,          
5b p-CO2CH3 130.6, 130.4 52.4(br) (a) 60.7 19.2 51.9(OMe)
    129.9,127.4,127.1,         167.1(C=O)
    125.6, 120.4        
5c p-Br 149.2,137.3,135.6, 52.0(br) (a) 60.4 18.9  
131.5, 130.1  
    129.5,126.9,125.2,          
    121.9, 118.7          
    155.6,145.0,137.6,          
5d p-NO2 135.7, 130.5 52.2(br) 43.0(br) 60.6 19.2  
    129.9,127.4,125.6,          
    124.8, 120.7          
5e H 150.6,137.7,136.1, 52.2(br) (a) 60.7 19.0  
130.4, 129.8  
    128.9,127.3,126.1,          
    125.6, 120.7          

(a) Not detected