Destroyer O chem

[utdent20]

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first of all can someone give a good explanation on understanding aromaticity? Huckel rule and the other rules, I don't know how to put them n use, maybe by giving an example would help.
2. # 56 on destroyer- 2 benzene rings undergo HCl , Why would B be the best answer? I mean C could work??
3. # 57. on destoryer-I don't understnad why 3 bromocycloheptene is the answer? I know ROOR and Light will go anti markankoff but it how to determine which one, why 3 and not 2 or 1.?
Lastly I need Need MAJOR help on IR and Hnmr and CNMR'. Like # 43 on on destoryer?

 

[OnlyDrilling]

for something to be aromatic is must follow huckels rule which mean it has to have 4n+2 electrons. so for a compound to be aromatic it must have 2, 6, 10, 14, 18 electrons. Lets say the compound had 4electrons(then it is non-aromatic). In order to be aromatic a compound must be cyclic (like benzene). It also has to be fully conjugated (so that electrons can delocalize and spread out). Benzene is fully conjugated because the ring has double bond, single bond, double bond, single bond, double bond, single bond. And the compound must be planar.
So for example something like pyrrole is aromatic because when you draw it out it has 6 electrons (2 electron from the Nitrogen count because they are inside the ring). That fulfills huckels rule. pyrrole is also planar and cyclic. And its fully conjugated (just go over the double and single bonds in the ring) (the lone pair on nitrogen is considered double bond then next to it is a single bond, then you have another double bond, then single, then double and last is single.
Hope that helps in some way.

 

[jdent]

first of all can someone give a good explanation on understanding aromaticity? Huckel rule and the other rules, I don't know how to put them n use, maybe by giving an example would help.
2. # 56 on destroyer- 2 benzene rings undergo HCl , Why would B be the best answer? I mean C could work??
3. # 57. on destoryer-I don't understnad why 3 bromocycloheptene is the answer? I know ROOR and Light will go anti markankoff but it how to determine which one, why 3 and not 2 or 1.?
Lastly I need Need MAJOR help on IR and Hnmr and CNMR'. Like # 43 on on destoryer?

56.The question tells u that it is low temp at low temp its kinetic contol and 1,2 addition . Look at answer explain fo r 2 possible carbocation intermediate. Hear 1,2 forms.
57. The double bond stays and gets lowest number and NBS removes the allylic.