0000004107 00000 n fast The substituents being tested are aniline, anisole, acetamide (acetanilide), and phenol. Prof. K. M. Muraleedharan The tube with the O-ring was connected to the sublimation apparatus. %���� The special reactivity of aromatic systems towards electrophiles arises mainly from two factors: the presence of π electron density above and below the plane of the ring - making it nucleophilic, and the drive to regain the aromatic character by opting for substitution as opposed to a simple addition reaction. ���|5����'�t��(� Z��|�#J:�����DQ� Ɍf���-7*PZ�=a�n�\H����$%גY�y3�s�[؜:KԷ3�~+Q�X�2����1u��DO�ˈ�ȧ��u�T� �>U-^J2�י� P ���D�d=� �{w� oF���VT�̽�^�t5��iNEh&�>iF�>s���`�##B����)���gDF��҂�d�® e���Am�o�,���\��l��:��w�:��b��)��gw��P]�p{8��v�o1j?W„�0�m�K�~s5Y�H,V�i+� �Y� H�]Yb)�NJ,�P���u ��~�9�� 0ֺ�� �`��EYM ��X�@ԄFאz� ~f��R!i �qE�) �45Ɗ"�"�w�.�a��A�V6�$��1K(A LRk���|[&�$�E�T�Ijȕ|�&a���\iR6�ɛ"M*�&�k�)Ҥ"lRY��q a� The objective of this experiment was to illustrate electrophilic aromatic substitution by synthesizing p-nitroanilide (as well as ortho) from acetanilide by nitration. Physical Properties & Hazards of Reagents/Products: (all taken from Sigma-Aldrich website)

Boiling point = 120.5°C The diffusion pump was connected to the water supply and turned on to 90 V. The cold trap of the apparatus was filled with Liquid nitrogen every hour of the experiment.

Density = 1.840 g/mL Justiniano, Priscilla Raiza N. @ ��

Part I (nitration of methyl benzoate) was carried out by Jenny.

Nitric acid

(oC)Methyl benzoateC8H8O2136.161.094-15198-200Methyl 2-nitrobenzoateC8H7NO4181.141.289-13104Methyl 3-nitrobenzoateC8H7NO4181.14-78-80289Methyl 3,5-dinitrobenzoateC8H6N2O6226.14544-106-109-Methyl 4-nitrobenzoateC8H7NO4181.15-94-96-1,4-DimethoxybenzeneC8H10O2138.161.0555-582131,4-Di-t-butyl-2,5-dimethoxybenzeneC16H26O2250.37-104-105-2-methyl-2-propanolC4H10O74.12-25.482.4Hazard Concentrated sulfuric acid and nitric acid are... ...Factors Affecting the Relative Rates of Electrophilic Aromatic _{i)�� ���U/��r'��ކ¡d��S��)A��IH�'��)V@���Uz�h�s�MC�6U��ַ���֞�?�M��_2J.�ד�����zzV����K�������3Za�34����1'$E�T(� ��3�?An ��� i�o+���T������YYEa`1���!��QL�*B� �!S�n��5�eXms� ���(3�Oy6�=�k9awц|�ae��^T���Y�J��G���h9��� L�;�7�n�����諭v�|Р�?�eݱ��.U�Q̅�U���WX�iz*�go�i��"���`�����������ū���S�K��(�d&� �Fj�ڗ����Av�@��O ��d��O���m�g0چ� $I��Y�;�j��ηъ��Q�+h�;������������)p&x�r8�2E�ᆪ�N�]�^��7%�|Qe�-X�@|YA\$aQCDH(���U ����8�+G4g}����Y��K�� 7�W.G�b�!ۉ`�j�Љj��r��I�Y��(���օ"�.���A���������J����Q4�6-�n"�r�����&d��5�-y�S�o� +�o���=��Ar~C�n1�tIs��DU������c�؞�p��u2��O�\9����t,�`2�Ly�~|Ьg-�umj��-�v��N����rM�J�����`җ���la������Oq�m�gJ�l��=ac�$R��>YB��'v5�wO���x���&�wS4�]���pv��緟ރ��Kl{MC̎)��Dv�h�(�B��.

16 x x x Probably needs further tweaking. 12 x x x Bromination with Br2 works fine but questions about product structure remain when pyridinium tribromide used. + E+ Some common electrophilic aromatic substitution reactions are: halogenation, nitration, sulfonation, Friedel-Crafts Acylation and Friedel-Crafts alkylation. moles vanillin = 0.3042 g/ 152.15 g/mol=0.00200. Melting point = 92-94°C AIM: The aim of this experiment is to carry out an addition reaction using trans-stilbene and bromine reagent to produce 1,2-dibromo-1,2-diphenylethane. 46 18

Inappropriate proportions <<810BC2E5DC1BDB4EA7DD177CB9AB4C8C>]>> This step is the most important factor that decides which substituents make benzene react faster. 0000001181 00000 n

Figure 2.

An electrophilic aromatic substitution reaction is the attack of an electrophile on an aromatic ring substituting for a proton.

AROMATIC COMPOUNDS ARE ALWAYS FOLLOWS THE SUBSTITUTION REACTION BECAUSE OF THE STABILITY OF THE BENZENE RING. o-nitroacetanilide