2-Methoxyethoxymethyl chloride

{{Chembox

| ImageFile = Methoxyethoxymethyl chloride.svg

| ImageSize =

| ImageAlt =

| IUPACName =

| OtherNames =

|Section1={{Chembox Identifiers

| CASNo = 3970-21-6

| ChemSpiderID = 69995

| EC_number = 223-589-8

| UNII = A5RRM67QUG

| PubChem = 77590

| StdInChI=1S/C4H9ClO2/c1-6-2-3-7-4-5/h2-4H2,1H3

| StdInChIKey = BIAAQBNMRITRDV-UHFFFAOYSA-N

| SMILES = COCCOCCl

}}

|Section2={{Chembox Properties

| C=4|H=9|Cl=1|O=2

| MolarMass =

| Appearance = colorless liquid

| Density = 1.094 g cm⁻³

| MeltingPt =

| BoilingPtC = 50-52

| BoilingPt_notes = 13 mm Hg

| Solubility = }}

|Section3={{Chembox Hazards

| GHS_ref={{cite web |title=2-Methoxyethoxymethyl chloride |url=https://pubchem.ncbi.nlm.nih.gov/compound/77590#section=Safety-and-Hazards |website=pubchem.ncbi.nlm.nih.gov |language=en}}

| GHSPictograms = {{GHS02}}{{GHS07}}{{GHS08}}

| GHSSignalWord = Danger

| HPhrases = {{H-phrases|226|302|315|319|335}}

| PPhrases = {{P-phrases|203|210|233|240|241|242|243|261|264|264+265|270|271|280|301+317|302+352|303+361+353|304+340|305+351+338|318|319|321|330|332+317|337+317|362+364|370+378|403+233|403+235|405|501}}

| MainHazards =

| FlashPt =

| AutoignitionPt = }}

}}

2-Methoxyethoxymethyl chloride is an organic compound with formula {{chem2|CH3OCH2CH2OCH2Cl}}. A colorless liquid, it is classified as a chloroalkyl ether. It is used as an alkylating agent. In organic synthesis, it is used for introducing the methoxyethoxy ether (MEM) protecting group.{{cite book |doi=10.1002/047084289X.rm100 |chapter=2-Methoxyethoxymethyl Chloride |title=Encyclopedia of Reagents for Organic Synthesis |year=2001 |last1=Wuts |first1=Peter G. M. |isbn=0471936235 }} MEM protecting groups are generally preferred to methoxymethyl (MOM) protecting groups, both in terms of formation and removal.

Typically, the alcohol to be protected is deprotonated with a non-nucleophilic base such as N,N-diisopropylethylamine (DIPEA, Hunig's base) in dichloromethane followed by addition of 2-methoxyethoxymethyl chloride.{{Cite journal|last1 = Corey|first1 = E. J.|last2 = Gras|first2 = Jean-Louis|last3 = Ulrich|first3 = Peter|date = 1976-03-01|title = A new general method for protection of the hydroxyl function|journal = Tetrahedron Letters|volume = 17|issue = 11|pages = 809–812|doi = 10.1016/S0040-4039(00)92890-9}} {{Cite journal|last1 = Lee|first1 = Hong Myung|last2 = Nieto-Oberhuber|first2 = Cristina|last3 = Shair|first3 = Matthew D.|date = 2008-12-17|title = Enantioselective Synthesis of (+)-Cortistatin A, a Potent and Selective Inhibitor of Endothelial Cell Proliferation|journal = Journal of the American Chemical Society|volume = 130|issue = 50|pages = 16864–16866|doi = 10.1021/ja8071918|issn = 0002-7863|pmid=19053422| bibcode=2008JAChS.13016864L | s2cid=207132632 }}

File:MOMDepr.png

The MEM protecting group can be cleaved (deprotection) with a range of Lewis and Bronsted acids.{{Cite journal|last1=Amano|first1=Seiji|last2=Takemura|first2=Noriaki|last3=Ohtsuka|first3=Masami|last4=Ogawa|first4=Seiichiro|last5=Chida|first5=Noritaka|date=1999-03-26|title=Total synthesis of paniculide A from d-glucose|journal=Tetrahedron|volume=55|issue=13|pages=3855–3870|doi=10.1016/S0040-4020(99)00096-4}}