Question

are these correct? if not, can you explain? thanks!

1. Provide either the Name or Structure for the Following Chemicals (6 points). OH OH a. o-bromophenol Pyridine 3-ethylbenzoic acid 2. Circle the aromatic molecules (8 points) -CH3 3. The following structure is a derivative of purine, a structure of great biological importance. For the three labeled nitrogen atoms, classify the hybridization of each nitrogen lone pair. (3 points) Na Sp3 N HON I- ZZ

Answer 1

1. All answers are correct

2. Huckel's rule for aromaticity

(i) The system should be planar

(ii) The system should be conjugated

(iii) The system should contain 4n+2 pi electrons
The system is not fully conjugated. So, non- aromatic —OH The system breaks the conjugation at the substituted position. So, non- aromatic. 3. CNCH3 (i) Planar (ii) conjugated (lone pair in the N will participate in the conjugation (111) 6 pi electrons (4 from double bonds + 2 from lone pair) So, aromatic. (i) Planar (ii) conjugated (iii) 10 pi electrons (4*2+2 = 10) So, aromatic.

8 pi = 4n pi electrons. So, non-aromatic

3. Na: it is forming 3 single bonds (1 with C and 2 with H atoms) and it has 1 lone pair. So, it needs 4 orbitals to form 3 sigma bonds and accommodate 1 lone pair. So, it is sp3 hybridized.

Nb: it is forming 3 single bonds (1 with H and 2 with C atoms) and it has 1 lone pair. So, it needs 4 orbitals to form 3 sigma bonds and accommodate 1 lone pair. So, it is sp3 hybridized.

Nc: it is forming 1 single bond, 1 double bond and it has 1 lone pair. Hence, it is forming 2 sigma bonds ( 1 from a single bond and 1 from the double bond) and 1 pi bond from the double bond. So, it needs 3 orbitals to form 2 sigma bonds and accommodate 1 lone pair. So, it is sp2 hybridized.