<jats:title>Abstract</jats:title><jats:p>Building upon the chemistry of Rh–N,S‐heterocyclic carbene complex, [(Cp*Rh)(L<jats:sub>2</jats:sub>)(1‐benzothiazol‐2‐ylidene)], <jats:bold>2</jats:bold> (Cp*=η<jats:sup>5</jats:sup>‐C<jats:sub>5</jats:sub>Me<jats:sub>5</jats:sub>; L=C<jats:sub>7</jats:sub>H<jats:sub>4</jats:sub>NS<jats:sub>2</jats:sub>) with various monoboranes‐Lewis adducts, we explored the chemistry of <jats:bold>2</jats:bold> with BH<jats:sub>3</jats:sub>⋅thf at elevated temperature. As a result, mild thermolysis of <jats:bold>2</jats:bold> with BH<jats:sub>3</jats:sub>⋅thf led to the formation of bis(sigma)borate [(η<jats:sup>4</jats:sup>‐C<jats:sub>5</jats:sub>Me<jats:sub>5</jats:sub>H)Rh(η<jats:sup>2</jats:sup>‐H<jats:sub>3</jats:sub>BL)], <jats:bold>3</jats:bold> and a bis‐zwitterionic species [Cp*RhS(BH<jats:sub>2</jats:sub>L<jats:sub>2</jats:sub>)], <jats:bold>4</jats:bold> with the concomitant release of BH<jats:sub>3</jats:sub>⋅bt (bt=benzothiazole). The RhS<jats:sub>3</jats:sub>C<jats:sub>2</jats:sub>N<jats:sub>2</jats:sub>B<jats:sub>2</jats:sub> atoms in <jats:bold>4</jats:bold> generates two six membered rings fused by a common Rh−S bond, which may be considered as a bicycle [4.4.0] cage at the rhodium center. In an effort to generate the iridium analogue of <jats:bold>3</jats:bold>, reaction of [Cp*IrCl<jats:sub>2</jats:sub>]<jats:sub>2</jats:sub> with Na[H<jats:sub>3</jats:sub>B(mbt)] (mbt=2‐mercaptobenzothiazole) was carried out that produced bis(sigma)borate complex [(η<jats:sup>4</jats:sup>‐C<jats:sub>5</jats:sub>Me<jats:sub>5</jats:sub>H)Ir(η<jats:sup>2</jats:sup>‐H<jats:sub>3</jats:sub>BL)], <jats:bold>1</jats:bold>. The solid state X‐ray structures of <jats:bold>1</jats:bold> and <jats:bold>3</jats:bold> showed that the Cp*H ligand coordinated to the metal center in a η<jats:sup>4</jats:sup>‐fashion. In compound <jats:bold>3</jats:bold>, the methyl group is oriented towards rhodium center, whereas it is away from Ir center in <jats:bold>1</jats:bold>. In addition, the DFT computations were performed to shed light on the bonding and electronic structures of these compounds.</jats:p>