Section A
Q1. Answer the following:
(a) What are sydnones? Draw a representative structure.
(b) With a suitable example show 'Norrish Type-II' cleavage reaction.
(c)
Show the mechanism for the following reaction:
2H3C-C-CH3 xrightarrow{HCl} H3C-C-CH=C-CH3 + H2O || || O O CH3
(d)
Mention the product in the given reaction:
CH3CH2CH2 - C - H + BrCH2CO2CH2CH3 xrightarrow{ ext{(i) Zn}} ext{(ii) } H2O^*
(e) Also provide mechanism of the above reaction. How 2,3-dimethyl-2,3-butanediol can be converted to 3,3-dimethyl-2-butanone? Suggest the mechanism of the involved reaction.
(f)
Identify A and B.
C=C xrightarrow{OsO4} A xrightarrow{ ext{Aqueous ethanolic } NaHSO3 ext{ solution}} B + (HO)_2OsO_2
(g) Explain why di-t-butoxycarbene is unreactive.
(h) The rate of hydrolysis of (CH3)_3CBr in 50% aqueous methanol is thousand times faster than that in pure methanol - explain.