Nitrogen selenium—oxygen bonds

The SRN1 process has proven to be a versatile mechanism for replacing a suitable leaving group by a nucleophile at the ipso position. This reaction affords substitution in nonactivated aromatic (ArX) compounds, with an extensive variety of nucleophiles ( u ) derived from carbon, nitrogen, and oxygen to form new C—C bonds, and from tin, phosphorus, arsenic, antimony, sulfur, selenium, and tellurium to afford new C-heteroatom bonds. 

In bonds between carbon and nitrogen, phosphorus, oxygen, sulfur, selenium, or the halogens, the carbon is made more positive —E )... 

Fig. 2 Ball and stick representations (Mercury 3.5) of the crystal structure of MEMKEU, the phosphate of thiamin, a vitamin of the B complex, wherein sulfur forms two chalcogen bonds dotted blue lines) thanks to the entrance of chloride and phosphate anions on the extended covalent bonds at sulfur SENGOH, 2-phenyl-l,2-2//-benzisoselenazole-3-one wherein selenium forms one directional chalcogen bond. CSD Refcodes and the Normalized contacts Nc, see onwards) are given. Color code gray, carbon sky-blue, nitrogen red, oxygen ocher, phosphorus light yellow, sulfur green, chlorine dark yellow, selenium...

Only for a few organozinc compounds, in which in addition to the zinc-carbon bond a zinc-heteroatom bond other than oxygen or nitrogen is present, have structures in the solid state been determined. These structures include those of organozinc compounds in which, in addition to the zinc-carbon bond, a zinc-sulfur, zinc-selenium, zinc-phosphorus or zinc-arsenic bond is present. 

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