Organochalcogen Multication Species

VALENTINE G. NENAJDENKO,a NIKOLAY E. SHEVCHENKO, 3 ELIZABETH S. BALENKOVAa AND IGOR V. ALABUGIN6 

N2 and the oxygen atoms are connected through a formal triple bond, the 0-0 distance in the 022+ dication, 1.073 A20 22 is the shortest known 0-0 distance,23 which is 0.134 A shorter than the bond in molecular oxygen and is considered to be the shortest bond between any two heavy atoms.21 For heavy chalcogens 7i-overlap of a triple bond becomes less efficient with longer bond distances. 

The most important of organic chalcogen dications are disulfonium dications (also called dithioether dications) - compounds with two positively charged sulfonium atoms connected by a single bond. 

2-dications - unique compounds with two cationic centers located at two directly connected atoms have unusual structure and reactivity. Despite the extremely strong electrostatic repulsion of the two positive charges, these compounds often possess remarkable kinetic stability. The rapid development of chemistry of 1,2-dications was facilitated by several excellent reviews and features articles dealing with small gas phase 1,2-dications as well as with certain types of organic dications containing C -C (see ref. 10), (see 

Depending on the initial connectivity, removal of two electrons from two chalcogen atoms may lead to the formation of a single (A), a double (B) or a triple (C) bond. Surprisingly, there are no experimental examples that correspond to case B although such species are possible intermediates in monoox- 

N2 and the oxygen atoms are connected through a formal triple bond, the 0-0 

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