Synthetic studies pertaining to the 2,3-pyridyne and 4,5-pyrimidyne

Abstract

We report synthetic studies pertaining to two heterocyclic aryne intermediates: the 2,3-pyridyne and the 4,5-pyrimidyne. First, a 2,3-pyridyne precursor was readily accessed from 2-pyridone using a known procedure. Subsequently, 2,3-pyridyne generation and trapping were used to access several functionalized pyridines in a regioselective manner. In addition, we report synthetic routes to two isomeric silyltriflates, which were intended to serve as precursors to the 4,5-pyrimidyne. Consecutive 4,5-pyrimidyne generation and trapping experiments were ultimately deemed unfruitful. We expect these findings will promote the use of 2,3-pyridyne and other heterocyclic arynes as building blocks for the synthesis of functionalized heterocycles.

Synthesis of Uracil-Iodonium(III) Salts for Practical Utilization as Nucleobase Synthetic Modules

“…Similarly, uracilyne 14 could not be generated from iodouracil [50]. In a more recent report, Garg et al attempted to generate pyrimidyne from silyltriflate precursors, but failed in the result [51].…”

Discussion Addendum for: The Direct Acyl-Alkylation of Arynes. Preparation of Methyl 2-(2-acetylphenyl)acetate

“…The chemistry of pyrimidynes has also been investigated, but there have been no reports of their successful formation. 40…”

Missing Reactivity of Trimethylsilyl Reagents: Dehalogenative Activation Enabling One-Pot Generation of Aryne from 2-Iodophenol

“…In order to investigate which element was attached to the C ipso -position of the iodine atom after the unprecedented dehalogenative reaction, we designed a Diels-Alder reaction between an aryne and 1,3-diphenylisobenzofuran as a model reaction (Table 1). [24][25][26][27][28][29][30][31][32][33][34][35][36] We hypothesised that if the C ipso position on the halogenated arenes was anionically activated by abstraction of a halogen atom by a fluoride-activated trimethylsilyl compound as with a carbanion equivalent, such as Table 1. Diels-Alder reactions between an aryne and 1,3-diphenylisobenzofuran.…”