In today's world, Isothiocyanate has gained special relevance in different areas of society. Whether in politics, economics, technology, culture or everyday life, Isothiocyanate has become a recurring and impactful topic of conversation. Its implications and repercussions have generated debates, analyzes and research that seek to understand its meaning and scope. From different perspectives, Isothiocyanate has influenced decision making and the way people interact with each other. In this article, we will explore the impact of Isothiocyanate and how it has shaped our current reality.
Chemical group (–N=C=S)
In organic chemistry, isothiocyanate is a functional group as found in compounds with the formula R−N=C=S. Isothiocyanates are the more common isomers of thiocyanates, which have the formula R−S−C≡N.
The N=C and C=S distances are 117 and 158 pm. By contrast, in methyl thiocyanate, N≡C and C−S distances are 116 and 176 pm.
Typical bond angles for C−N=C in aryl isothiocyanates are near 165°. Again, the thiocyanate isomers are quite different with C−S−C angle near 100°. In both isomers the SCN angle approaches 180°.
Synthesis
Allyl thiocyanate isomerizes to the isothiocyanate:
CH2=CHCH2SCN → CH2=CHCH2NCS
Isothiocyanates can be prepared by degradation of dithiocarbamate salts, e.g. induced with lead nitrate.
A related method is tosyl chloride-mediated decomposition of dithiocarbamate salts.
Isothiocyanates may also be accessed by the fragmentation reactions of 1,4,2-oxathiazoles. This methodology has been applied to a polymer-supported synthesis of isothiocyanates.
Reactions
Isothiocyanates are weak electrophiles, susceptible to hydrolysis. In general, nucleophiles attack at carbon:
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