Methyl cyanoformate explained

Methyl cyanoformate is the organic compound with the formula CH₃OC(O)CN. It is used as a reagent in organic synthesis as a source of the methoxycarbonyl group,^[1] in which context it is also known as Mander's reagent. When a lithium enolate is generated in diethyl ether or methyl t-butyl ether, treatment with Mander's reagent will selectively afford the C-acylation product.^[2] Thus, for enolate acylation reactions in which C- vs. O-selectivity is a concern, methyl cyanoformate is often used in place of more common acylation reagent like methyl chloroformate.

Methyl cyanoformate is also an ingredient in Zyklon A. It has lachrymatory effects.^[3]

References

1. Simon R. Crabtree, W. L. Alex Chu, Lewis N. Mander "C-Acylation of Enolates by Methyl Cyanoformate: An Examination of Site- and Stereoselectivity"Synlett 1990; 1990: 169–170.
2. Crabtree. Simon R.. Chu. W. L. Alex. Mander. Lewis N.. 1990. C-Acylation of Enolates by Methyl Cyanoformate: An Examination of Site- and Stereoselectivity. Synlett. en. 1990. 3. 169–170. 10.1055/s-1990-21025. 0936-5214.
3. Book: Sartori . Mario . The War Gases . 1939 . 100. D. Von Nostrand. New York.