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

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.

SUBMITTER: Kurup SS

PROVIDER: S-EPMC8739204 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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

Kurup Sudheer S SS Nasser Sandra S Ward Cassandra L CL Groysman Stanislav S

Acta crystallographica. Section E, Crystallographic communications 20220101 Pt 1

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 ...[more]

PMID: 35079433

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