Light-Induced Metal-Free Generation of Cyanocarbenes from Alkynyl Triazenes for the Synthesis of Nitrile Derivatives.

The chemistry of alkynyl triazenes is an emerging field for organic chemists and especially acid-induced nucleophilic functionalizations, either directly, or after a prior reaction towards aromatic triazenes under extrusion of nitrogen, paved the way for fruitful strategies. In contrast, the chemical behavior of alkynyl triazenes upon irradiation with light is still unknown. Herein we present the first photoactivation of alkynyl triazenes that triggers an uncommon reactivity pattern involving the cleavage of the N1-N2 bond of the triazene moiety resulting in a unique approach to cyanocarbenes from a readily available, stable, and insensitive precursor.

Guanidines from 'toxic substances' to compounds with multiple biological applications--detailed outlook on synthetic procedures employed for the synthesis of guanidines.

Guanidines to begin with, were thought of being harmful substances associated with medical ailment. With the advent of World War I and the impact it left on the populations at large research focus was shifted, towards polymer synthesis and that too on plastics and rubbers which were mostly employed in various artillery equipments. In the surge, to get plastics and rubbers with enhanced mechanical properties, many variedly substituted guanidines used as accelerators in vulcanization of polymers were synthesized using different procedures.