Question

Label the following as activating (A) or deactivating (D), and then also as ortho/para directors (OP) or meta directors (M). Write the answer below each group. N "Here with other ty A/D? = = = = OP/M? = f) Using resonance structures, explain why a nitro group is "meta-directing" (i.e. does the nitro group actually affect the meta positions?) g) As mentioned in class, the halogens are a bit anomalous as substituents on the aromatic ring: they are deactivating groups, but are also ortho/para directors. Fluorine is especially interesting; even though it is an "ortho/para director,” it mainly directs to the para position (o:p ratio = 86:13). Propose an explanation for this. Hint: Remember why halide substituents are interesting in the first place, and keep in mind that an iodine substituent has 50:50 o:p ratio. i.e. don't say sterics. EAS "X" 13% 87%

Answer 1

op directing groups is Frese are the elechon donar group which directs the o and þ products. im directing groups. These are the clechon with drawing groups which decactivates the sing and direct the m- product.

F is o and b directing through + R effect but it withdrawe election density by - I effect. Therefore, gt with drow elecson density through a bond. Because fis most : elechonegative - I effect a distance the f st means nearer atom to more efechon de Hicrant due to - I effect.. Therefore, it give more 87% para product and less 13% ortho propuct because of the position is near to f and p is far from F. Mear Mear