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Substitution of fluorine in M[C₆F₅BF₃] with organolithium compounds: distinctions between O- and N-nucleophiles.

ABSTRACT: Borates M[C₆F₅BF₃] (M = K, Li, Bu₄N) react with organolithium compounds, RLi (R = Me, Bu, Ph), in 1,2-dimethoxyethane or diglyme to give M[4-RC₆F₄BF₃] and M[2-RC₆F₄BF₃]. When R is Me or Bu, the nucleophilic substitution of the fluorine atom at the para position to boron is the predominant route. When R = Ph, the ratio M[4-RC₆F₄BF₃]/M[2-RC₆F₄BF₃] is ca. 1:1. Substitution of the fluorine atom at the ortho position to boron is solely caused by the coordination of RLi via the lithium atom with the fluorine atoms of the BF₃ group. This differs from the previously reported substitution in K[C₆F₅BF₃] by O- and N-nucleophiles that did not produce K[2-NuC₆F₄BF₃].

SUBMITTER: Shabalin AY

PROVIDER: S-EPMC5405681 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Substitution of fluorine in M[C6F5BF3] with organolithium compounds: distinctions between O- and N-nucleophiles.

Shabalin Anton Yu AY Adonin Nicolay Yu NY Bardin Vadim V VV

Beilstein journal of organic chemistry 20170412

Borates M[C6F5BF3] (M = K, Li, Bu4N) react with organolithium compounds, RLi (R = Me, Bu, Ph), in 1,2-dimethoxyethane or diglyme to give M[4-RC6F4BF3] and M[2-RC6F4BF3]. When R is Me or Bu, the nucleophilic substitution of the fluorine atom at the para position to boron is the predominant route. When R = Ph, the ratio M[4-RC6F4BF3]/M[2-RC6</su ...[more]

PMID: 28503205

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