Question

Consider the following chemical transformations:

a) use curved arrows to show the chemical transformation of each step in the following reactions

b) indicate which if the 4 patterns are used in each transformation

C-N-o are the second low devouts that can't love wore thou (4 orbitals. 2. Consider the following chemical transformations. A. Use curved arrows to show the chemical transformation of each step in the following reactions. B. Indicate which of the 4 patterns are used in each transformation. 2 . W 0-H HO: H-5 0-H H₂O Wyo "NH₂ н-он T NH2 HH My-O H: OH NHA NH, H-0 0-H VONH V 6- :0: Н H-A Меон H-0 0 Me H-ö Ö-Me hemiacetal H-4 acetal Page 2

Answer 1

These reactions are example of addition elimination reactions on carbonyl groups and acetal formation. The first pattern is attack of nucleophile on carbonyl group followed by elimination of either of ammonia or water depending on the reaction.The other aspects involve the affinity of oxygen of carbonyl group for H+ being a very good nucleophile.

H. LN-me NH n ME Me-NH₂ Me Na 'N-me Ho N-me H₂O: K-9 I-2 N-me : + H-A + H₂O: I NH NH, NH₃ 00 Q) H g teme MeOn -0 me kao H-A me Meon. Herniacetal meo: ome Acetal

The u patterns followed in each of the transformation are 11 Attack on 0 (carbonyl) & by a nucle of by a nucleophile. 3) ck on ti of an acid (Affinity for it) Removal of water (H₂O) nation of a leaning group (ring and :ötz) from site of carbonyl attact. (carbonyl formation) mino The above two are addition - elimination reaction Third one is a kind of but more appropriately it is acetal and hemia cetal formation reaction. But hemacete are generally very unstable so they are kind considered as intermediates 6