Michael Addition–Aromatization Reaction of Dienylimines Bearing a Leaving Group and Its Application to the Preparation of Thiol-Selective Labeling Reagents Capable of Forming Strong Carbon–Sulfur Bonds

Abstract

The reaction of a dienylimine with thiols was found to proceed smoothly to afford the corresponding indolines bearing aromatic carbon-sulfur bonds as a result of a Michael addition-aromatization sequence. Furthermore, this reaction was applied to the development of fluorogenic dienylimines that could be used as thiol-selective fluorescent labeling reagents.

Stereoselective Construction of Methylenecyclobutane-Fused Indolines through Photosensitized [2+2] Cycloaddition of Allene-Tethered Indole Derivatives

“…To meet the demand for such frameworks, new methods of synthesizing diverse indoline derivatives are needed. To date, a number of synthetic methods have been reported for this important class of compounds, whereas there has been much less exploration of cyclobutane-fused indolines. , The [2+2] photocycloaddition using 1-acylindoles as components is an exception. It has been extensively examined to access the cyclobutane-fused compounds. − …”

Formation of anti‐Bredt‐type azabicyclo[4.2.0]octene frameworks through photochemical intramolecular [2+2] cycloaddition between indole and a distal double bond of allene

“…Therefore, many efforts have been dedicated to the preparation of this particular molecular frameworks so far [8–10]. Whereas the preparative method for indolines fused with 5‐ or 6‐membered ring has wide variety among these traditional processes [8], those for cyclobutane‐fused indolines have been much less explored [11–17].…”