1,2-Dihydro-1,2-azaborine is an aromatic chemical compound with properties intermediate between benzene and borazine. Its chemical formula is CBNH. It resembles a benzene ring, except that two adjacent carbons are replaced by nitrogen and boron, respectively. Several other 1,2-azaborines have been synthesized.

Preparation

After decades of failed attempts, the compound was synthesized in 2008 and reported in January 2009.Stu Borman. "Long-Sought Benzenelike Molecule Created: Aromaticity of organic-inorganic hybrid resembles benzene's." C&EN January 5, 2009 Volume 87, Number 01 p. 11

One of the synthetic steps is a ring-closing metathesis (RCM) reaction:TBS = tert-butyldimethylsilyl, step 2 RCM = ring-closing metathesis using Grubbs' catalyst, step 3 organic oxidation using palladium on carbon, step 4 reduction LiBHEt, step 5 conversion to piano stool complex as protective group with chromium carbonyl derivative, step 6 cleavage N-TBS bond HF, step 7 deprotection with triphenylphosphine

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