To a suspension of Starting Material in methanol, thionylchloride  was added dropwise at 5°C under a nitrogen atmosphere. The reaction was refluxed for until starting material is consumed by stirring under nitrogen. The solvent and excess thionylchloride were removed by distillation. The residue solid was washed with dry diethylether/E.A.and dried to get product

You can refer to this article too 

http://chemport.cas.org/cgi-bin/cp_sdcgi?j5g3uXRFFkCZp8rf5tM12YXtlvKfwmItZZt@29cpXhKCdCyNCfppvvsyINhTS8oiq9oJeu4gA9JksF17lutUSMkhcyJbmp6UuSWP2bQSf9_V@Y89LBqgkXbdqqbbzpdeaCK5fhRpSgoQSMmktREz2Yp@oI3_rp2uC52Wyh9gs4

Moreover in general:

If you want a ester of two carbons, use Ethanol, if only one carbon use Methanol.

Using SOCl2 makes the reaction fast as it makes acyl chloride first and then ester

Other you can use H2SO4 With appropriate alcohol (methanol, ethanol). and reflux.

Hopefully my answer would help you.

Note: Add SOCl2 slowly and make setup your R.B.F in Ice.

Sir Can I know How to convert Amino Acid Carboylic gropu into Ester

Hi, My answer is in the attached file. But I recommend the Organic Chemistry Portal.

The link provided.

http://www.organic-chemistry.org/synthesis/C1O/esters/esterifications.shtm

To a suspension of Starting Material in methanol, thionylchloride  was added dropwise at 5°C under a nitrogen atmosphere. The reaction was refluxed for until starting material is consumed by stirring under nitrogen. The solvent and excess thionylchloride were removed by distillation. The residue solid was washed with dry diethylether/E.A.and dried to get product

You can refer to this article too 

http://chemport.cas.org/cgi-bin/cp_sdcgi?j5g3uXRFFkCZp8rf5tM12YXtlvKfwmItZZt@29cpXhKCdCyNCfppvvsyINhTS8oiq9oJeu4gA9JksF17lutUSMkhcyJbmp6UuSWP2bQSf9_V@Y89LBqgkXbdqqbbzpdeaCK5fhRpSgoQSMmktREz2Yp@oI3_rp2uC52Wyh9gs4

Moreover in general:

If you want a ester of two carbons, use Ethanol, if only one carbon use Methanol.

Using SOCl2 makes the reaction fast as it makes acyl chloride first and then ester

Other you can use H2SO4 With appropriate alcohol (methanol, ethanol). and reflux.

Hopefully my answer would help you.

Note: Add SOCl2 slowly and make setup your R.B.F in Ice.

You can find more here

Molecules 2008, 13, 1111-1119; DOI: 10.3390/molecules13051111

A Convenient Synthesis of Amino Acid Methyl Esters

http://www.mdpi.com/1420-3049/13/5/1111

Dear Sundeep Pothula,

Esterification of carboxyl groups in amino acid is not the same as usual esterification reactions because in this case you have amino group which can also react with carboxyl groups. I think it will be better if you follow the method suggested by Raju Thombal. Just keep in mind that anyhow you have to avoid or minimise the reaction in between NH2 and COOH groups.

Good luck.

Try methyl (or ethyl) orthoesters, or O-methyl (or ethyl) isoureas. The isoureas worked well in my experience on small molecules (not amino acids), but purifying ureas can be tedious.

My above answer was meant to read " but purifying away the side product urea can be tedious"

AcCl/MeOH  You can get methylester

with trimethylsilyldiazomethane u can get methyl ester

Dissolve acid in absolute alcohol and after that saturate solution with HCl - gas. 

The basic concept in case for the esterification of COOH in amino acids is the protection of amino functionality. And this could be acheived in any acidic conditions, as it will form the salt (eg. HCl salt) and keep amino group unscathed. 

few examples are

1) HClO4/t-BuOAc for -COO-t-Bu

2) MeSO3H/ BnOH for COOBn

Best luck! 

Simply take amino acid in methanol(for methyl ester) or ethanol (for ethyl ester), keep under ice bath, add slowly dropwise thionyl chloride, after completion of addition remove ice bath and stirr at rt for overnight (or reflux for 3 hr); after completion of reaction remove all volatiles, wash with ether and dried to get the ester of amino acid (where amine in salt form). If you want free amine basify it with NaHCO3 aqueous solution and extract in ethyl cateate.

dissolve amino acid in ethanol and cool it to zero degree.after that drop wise add SOCl2 with stirring and stirr for one more hour.then reflux it for 12 hours and dry on rotary evaporator.

Thanks every one for your reply. 

Sir, Can we use Thionyl chloride for synthesis of L serine methyl ester from L serine.

And is there any method for separating L serine and L serine methyl ester from the product mixture.

Molecules 2008, 13, 1111-1119; DOI: 10.3390/molecules13051111

this is the best method ive gone through and even used in my lab.

hello...  Is there any link for an article for the experiment which utilizes SOCL2 please

amino acid 0.1 mol chlorotl sialne 0.2 mol in mthanol stirr overnight. i find this method very gud abd high yield. thanx