Synthesis and Versatile Utilization of 2‐Pyridyl and Pyrimidyl‐Related Reagents

Abstract

Active (thio)esters and amides were prepared from carboxylic acids and several reagents containing 2‐pyridyl or pyrimidyl moiety. Active (thio)carbonates, thionocarbonate, and thiourea were prepared from (thio)phosgene and 2‐hydroxypyridine or 2‐mercaptopyridine. The acylation of active (thio)esters and amides containing 2‐pyridyl or pyrimidyl groups with various organometallics afforded ketones, aldehydes, esters, amides, and β‐keto esters. The alkoxycarbonylation of active (thio)carbonates with Grignard reagents and amines afforded esters and carbamates, respectively. Active di(thiono)carbonates and thiourea containing the 2‐pyridyl or pyrimidyl moiety have been used in the dehydration of carboxylic acids/alcohols or aldoximes, dehydrosulfurization of thioureas, and (thio)carbonyl transfer of diols or amines to produce esters or nitriles, carbodiimides, cyclic carbonates or isothiocyanates, respectively.

Structures of S-(pyridin-2-yl) 4-nitrobenzothioate, S-(pyridin-2-yl) 4-methylbenzothioate and S-(pyridin-2-yl) 4-methoxybenzothioate: building blocks for low-symmetry multifunctional tetrapyrroles

“…These compounds were also utilized to generate 2-ketopyrroles (Nicolau et al, 1981). Their versatility was recently highlighted (Lee, 2020). The developments that have led to this point now enable the generation of diverse substitution patterns for both porphyrins (Rao et al, 2000;Senge, 2011) and chlorins (Laakso et al, 2012;Ra et al, 2015;Senge et al, 2021).…”