Methyl isothiocyanate is the

organosulfur compound Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur der ...

with the

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ...

CH₃N=C=S. This low melting colorless solid is a powerful

lachrymator Tear gas, also known as a lachrymatory agent or lachrymator (), sometimes colloquially known as "mace" after the Mace (spray), early commercial self-defense spray, is a chemical weapon that stimulates the nerves of the lacrimal gland in the ey ...

. As a precursor to a variety of valuable bioactive compounds, it is the most important organic

isothiocyanate In organic chemistry, isothiocyanate is a functional group as found in compounds with the formula . Isothiocyanates are the more common isomers of thiocyanates, which have the formula . Occurrence Many isothiocyanates from plants are produce ...

in industry.

Synthesis

It is prepared industrially by two routes. Annual production in 1993 was estimated to be 4,000 tonnes. The main method involves the thermal rearrangement of methyl thiocyanate: :CH₃S−C≡N → CH₃N=C=S It is also prepared via with the reaction of

methylamine Methylamine, also known as methanamine, is an organic compound with a formula of . This colorless gas is a derivative of ammonia, but with one hydrogen atom being replaced by a methyl group. It is the simplest primary amine. Methylamine is sold ...

with

carbon disulfide Carbon disulfide (also spelled as carbon disulphide) is an inorganic compound with the chemical formula and structure . It is also considered as the anhydride of thiocarbonic acid. It is a colorless, flammable, neurotoxic liquid that is used as ...

followed by oxidation of the resulting

dithiocarbamate In organic chemistry, a dithiocarbamate is a chemical compound with the general formula . It contains the functional group with the Chemical structure, structure . It is the analog of a carbamate in which both oxygen atoms are replaced by sulfur ...

with

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscosity, viscous than Properties of water, water. It is used as an oxidizer, bleaching agent, and antiseptic, usua ...

. A related method is useful to prepare this compound in the laboratory. MITC forms naturally upon the enzymatic degradation of glucocapparin, a

glucoside A glucoside is a glycoside that is chemically derived from glucose. Glucosides are common in plants, but rare in animals. Glucose is produced when a glucoside is hydrolysed by purely chemical means, or decomposed by fermentation or enzymes. Th ...

found in

caper ''Capparis spinosa'', the caper bush, also called Flinders rose, is a perennial plant that bears rounded, fleshy leaves and large white to pinkish-white flowers. The taxonomic status of the species is controversial and unsettled. Species with ...

Reactions

A characteristic reaction is with amines to give methyl

thiourea Thiourea () is an organosulfur compound with the formula and the structure . It is structurally similar to urea (), with the oxygen atom replaced by sulfur atom (as implied by the '' thio-'' prefix). The properties of urea and thiourea differ s ...

s: :CH₃NCS + R₂NH → R₂NC(S)NHCH₃ : Other nucleophiles add similarly.

Applications

Solutions of MITC are used in agriculture as soil

fumigant Fumigation is a method of pest control or the removal of harmful microorganisms by completely filling an area with gaseous pesticides, or fumigants, to suffocate or poison the pests within. It is used to control pests in buildings (structural ...

s, mainly for protection against fungi and nematodes. MITC is a building block for the synthesis of 1,3,4-thiadiazoles, which are

heterocyclic compound A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). Heterocyclic organic chemistry is the branch of organic chemistry dealing with the synthesis, proper ...

s used as herbicides. Commercial products include "Spike", "Ustilan," and "Erbotan." Well known pharmaceuticals prepared using MITC include Zantac and

Tagamet Cimetidine, sold under the brand name Tagamet among others, is a histamine H2 receptor antagonist that inhibits stomach acid production. It is mainly used in the treatment of heartburn and peptic ulcers. With the development of proton pump i ...

Suritozole Suritozole (MDL 26,479) is an investigational cognition enhancer. It acts as a partial inverse agonist at the benzodiazepine receptor site on the GABAA ion channel complex, but does not have either anxiogenic or convulsant effects, unlike other ...

is a third example. MITC is used in the Etasuline patent (Ex2), although the compound is question (Ex6) is with EITC.

Safety

MITC is a dangerous

as well as being poisonous.

References

{{Cruciferous Biochemistry Methyl esters Isothiocyanates Lachrymatory agents

Synthesis

Reactions

Applications

Safety

See also

References