Synthesis and structure of a new bulky bis-(alkoxide) ligand on a terphenyl platform

Sudheer S Kurup; Sandra Nasser; Cassandra L Ward; Stanislav Groysman

doi:10.1107/S2056989021013438

Synthesis and structure of a new bulky bis-(alkoxide) ligand on a terphenyl platform

Acta Crystallogr E Crystallogr Commun. 2022 Jan 1;78(Pt 1):92-96. doi: 10.1107/S2056989021013438.

Authors

Sudheer S Kurup¹, Sandra Nasser¹, Cassandra L Ward², Stanislav Groysman¹

Affiliations

¹ Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, USA.
² Lumigen Instrument Center, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, USA.

Abstract

A new sterically bulky chelating bis-(alkoxide) ligand 3,3'-([1,1':4',1''-terphen-yl]-2,2''-di-yl)bis-(2,2,4,4-tetra-methyl-pentan-3-ol), (H₂[OO]^tBu), was prepared in a two-step process as the di-chloro-methane monosolvate, C₃₆H₅₀O₂·CH₂Cl₂. The first step is a Suzuki-Miyaura coupling reaction between 2-bromo-phenyl-boronic acid and 1,4-di-iodo-benzene. The resulting 2,2''-di-bromo-1,1':4',1''-terphenyl was reacted with ^t BuLi and hexa-methyl-acetone to obtain the desired product. The crystal structure of H₂[OO]^tBu revealed an anti conformation of the [CPh₂(OH)] fragments relative to the central phenyl. Furthermore, the hydroxyl groups point away from each other. Likely because of this anti-anti conformation, the attempts to synthesize first-row transition-metal complexes with H₂[OO]^tBu were not successful.

Keywords: 3 d metals; alkoxide; chelating ligand; crystal structure.

Grants and funding

This work was funded by National Science Foundation grant CHE-1855681.