A robust and modular synthesis of ynamides

Abstract

A flexible, modular ynamide synthesis is reported that uses trichloroethene as an inexpensive two carbon synthon. A wide range of amides and electrophiles can be converted to the corresponding ynamides, importantly including acyclic carbamates, hindered amides, and aryl amides. This method thus overcomes many of the limitations of other approaches to this useful functionality.

Hexadehydro-Diels–Alder (HDDA)-Enabled Carbazolyne Chemistry: Single Step, de Novo Construction of the Pyranocarbazole Core of Alkaloids of the Murraya koenigii (Curry Tree) Family

“…Particularly noteworthy is the construction of the ynamide bond 24 in 16 via the 1,2-dichlorovinylsulfonamide 15 . 25 In our hands this strategy proved to be more reproducible and serviceable for the sulfonamide 14 than one using the ethynyl iodonium salt HC≡C(Ph)I + TfO − 26 . Heating 17 with β,β-dimethylacrolein followed by TBAF treatment to strip away the TMS and Ts groups completed this efficient synthesis of koenidine.…”

Synthesis of aminopyrazoles from sydnones and ynamides

“…First we proceeded with the preparation of the sulfonyl ynamides via the dichloroenamide approach reported by Anderson and coworkers, 33 which allowed a convenient large scale synthesis of the ynamide substrates. 34 Alternative popular synthetic routes to ynamides include copper-catalysed amidative cross-coupling processes.…”

Efficient Access to Multifunctional Trifluoromethyl Alcohols through Base‐Free Catalytic Asymmetric C−C Bond Formation with Terminal Ynamides

“…[13] Therecent introduction of avery practical two-step synthesis of terminal ynamides from tosylamides and trichloroethylene by Anderson and co-workers provided an excellent starting point for our study. [14] At the onset of this investigation, we employed N-ethynyl-N-butylbenzenesulfonamide (1)a nd other ynamides in several literature procedures previously developed for catalytic enantioselective alkynylations of carbonyl electrophiles. While these screening efforts were mostly unsuccessful, we were excited to find that asymmetric addition of an ynamide to trifluoroactophenone occurs in the presence of catalytic amounts of zinc triflate, N-methylephedrine,and excess Et 3 N or iPr 2 NEt.…”