# how to add a methyl group to a straight carbon chain

I mean like how can I convert ethane into propane, ethene into propene and like this further on

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Direct ethene to propene (ETP) conversion seems possible at 400 °C on mesoporous silica (M41) loaded with nickel ions.

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Note that I didn't know that either until now and just found it in a cursory search! –  Klaus Warzecha Mar 1 at 16:50

Why would you want an expensive process to convert cheap molecules into other cheap molecules? Brominate ethane, make the organo-lithium, displace methyl iodide. Epoxidize ethylene, react with methyl lithium, eliminate to the olefin. Silly.

Doing something cheap, easy, and fast on a huge scale with unwanted methane from oil wells to form a high energy density liquid for pipeline conveyance will make you rich. Methanol is marginal - and still can't be done. Perhaps methane plus air into titanium-silicalite (plus hydrogen peroxide, or cobalt- or vanadium-doped plus air) then that mixed product through ZSM-5 into aromatic gasoline. That could be exciting in various ways.

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Because I am in high school and I have to it on paper not in reality, this is on of the higher order thinking skills question that my school have to me. –  Armaan Mar 2 at 7:00
A. M. Schwartz, M. Petitjean, "[6.6]Chiralane: a remarkably symmetric chiral molecule," Symmetry: Culture and Science 19(4) 307-316 (2008). It is a molecule whose sense of chirality cannot be named, even in principle, mazepath.com/uncleal/schwart3.png When CAS and Agnew Chemie cannot name a bunch of chiral centers, I say "publish it." They said "no." It does not impact my income. –  Uncle Al Mar 3 at 19:09
Folks, I know you were likely just joking with each other, but someone reading your comments later might misconstrue them. –  jonsca Mar 4 at 8:22
Who reads organic chemistry? "8^>) Employment is EPA-expelled offshore. September 1969, Michigan State, 1200+ Majors Organic enrollment. June 1973, 15 BS/Chem graduated. Wanting it more than anything else is a good start. –  Uncle Al Mar 13 at 1:18

Firstly, you cant go ethane to propene, it should be propane.

Chemically, you can do it by following steps:

1. halogenate with $\ce{Cl}$ in UV.
2. then use $\ce{KCN}$ to make nitrile - it will replace $\ce{Cl}$.
3. hydrolyse it using $\ce{KOH}$.
4. then it will be a carboxylic acid.
5. reduce it using $\ce{LiAlH4}$ and then, you have got propane.

You can go for ethene the same way, but there will be complications.

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You haven't really done that, have you? Photochlorination of ethane will yield ethylchloride (btw suspect of being cancerogenic) plus butane (from the termination step of the radical reaction) plus chlorinated butane(s). $S_N1$ reactions of alkyl chlorides with sodium or potassium cyanide in DMSO do work in principle. Here, the boiling point of ethylchloride is 12 °C, the melting point of DMSO is 19 °C. Propionitrile to propionic acid looks ok, but what about the reduction? The reaction of propionic acid with $\ce{LiAlH4}$ will yield 1-propanol. –  Klaus Warzecha Mar 2 at 7:35