Need help with a few hydrocarbon conversions...?

Question

How can I convert:
1) Ethanol to 1-bromo propane
2) Ethene to methanal
3) 2-methyl propene to ethanal??
Thanks in advance.

Answer 1

1) Ethanol to 1-bromo propane

CH3CH2OH + PBr3 -> CH3CH2Br
CH3CH2Br + Mg -> CH3CH2MgBr
CH3CH2MgBr + HCHO -> CH3CH2CH2OH
CH3CH2CH2OH + PBr3 -> CH3CH2CH2Br

2) Ethene to methanal

CH2=CH2 + O3 -> ozonide
ozonide + Zn -> HCHO

3) 2-methyl propene to ethanal??
(CH3)2C=CH2 + O3 -> ozonide
ozonide + Zn -> (CH3)2C=O + HCHO
(CH3)2C=O + NaBH4 -> (CH3)2CHOH (isopropanol)
isopropanol + H2SO4 -> CH3CH2=CH2 (propene)
CH3CH2=CH2 O3 -> ozonide
ozonide + Zn -> CH3CHO (Ethanl) + HCHO