A Catalyst-Controlled Divergent Rearomatization of BN-Benzvalene.

Area of Science:

• Organic Chemistry
• Organometallic Chemistry
• Materials Science

Background:

• Benzvalene, a strained isomer of benzene, exhibits unique reactivity.
• Boron-nitrogen (BN) containing heterocycles are of interest in various chemical applications.
• Understanding rearrangement pathways is crucial for synthetic control.

Purpose of the Study:

• To investigate the thermal and metal-catalyzed rearomatization of BN-benzvalene.
• To explore selective synthesis of C5- and C3-functionalized 1,2-azaborines.
• To elucidate the mechanistic pathways governing these transformations.

Main Methods:

• Metal-catalyzed reactions with BN-benzvalene.
• Deuterium labeling studies.
• Density Functional Theory (DFT) calculations.

Main Results:

• Selective formation of C5-functionalized 1,2-azaborines, demonstrating a new molecular photoswitch system.
• Selective formation of C3-functionalized 1,2-azaborines, showcasing functional group transposition.
• Distinct reaction mechanisms identified for C5- and C3-isomer generation.

Conclusions:

• BN-benzvalene is a versatile precursor for synthesizing functionalized 1,2-azaborines.
• Metal catalysis offers selective control over isomer formation.
• The findings open avenues for novel molecular switches and functionalized heterocycles.