How are the following conversions effected
1. propanal into butanone
2. Hex-3-yne hexan-3-one
3. phenylmethanal into benzoic acid
4. phenylmethanal into benzoin

Explanation

1. propanal into butanone:
`underset(("Propanal"))(CH_(3)CH_(2)CHO)underset((ii)H^(+)//H_(2)O)overset((i)CH_(3)MgBr)tounderset(("Butan-2-ol"))(CH_(3)-CH_(2)-overset(OH)overset(|)(CH)-CH_(3))underset(O)overset(Con.HNO_(3))tounderset(("2 - Butanone"))(CH_(3)-CH_(2)-overset(O)overset(||)C-CH_(3)+H_(2)O)`
2. Hex-3-yne into hexan-3-one:
`underset(("Hex-3-yne"))underset(" ")(CH_(3)-CH_(2)-C-=C-CH_(2)-CH_(3))underset(H_(2)O)overset(HgSO_(4)//H_(2)SO_(4))tounderset(("Hexan-3-one"))(CH_(3)-cH_(2)-underset(O)underset(||)C-CH_(2)-CH_(2))-CH_(3)`
3. Phenylmethanal into benzoic acid:
`underset(("Benzaldehyde"))underset(("Phenyl methanal"))(C_(6)H_(5)CHO)underset((O))overset(OH^(Θ)//KMnO_(4))tounderset(("Benzoic acid"))underset(" ")(C_(6)H_(5)COOH)`
4. Phenyl methanal into benzoin:
`underset(("Phenyl methanol"))underset(("Benzaldehyde"))(C_(6)H_(5)-underset(O)underset(||)overset(H)overset(|)C+H-underset(O)underset(||)C)-C_(6)H_(5) overset(alc.KCN)tounderset(("Benzoin"))(C_(6)H_(5)-underset(OH)underset(|)(CH)-underset(O)underset(||)C-C_(6)H_(5))`