AlCl₃‐Promoted Ritter‐Type Ring‐Opening Reactions of γ‐Butyrolactone Fused Donor‐Acceptor Cyclopropanes with Wet Aliphatic Nitriles

Abstract

γ-Butyrolactone fused D-A cyclopropanes, when treated with aliphatic nitriles in the presence of water and aluminium(III) chloride, gave 3,4,5-trisubstituted γ-butyrolactones stereoselectively. The products are most likely produced [a] 593 through ring opening by nitriles followed by nucleophilic addition of water to the resulting nitrilium ion intermediates through a Ritter-type mechanism.products [6] and pharmaceutically relevant compounds [7] and hence a good number of approaches have been developed for the stereoselective synthesis of γ-butyrolactones. [8] It is also noteworthy that there are few reports in the literature on similar Ritter-type reactions of other types of D-A cyclopropanes with nitriles in the presence of water. [9] Scheme 1. Our previous work and an observation during the course of the work.

Tandem Dearomative/Rearomative (3 + 2) Annulation of Aroyl-Substituted Donor–Acceptor Cyclopropanes with Benzothiazoles

“…Silica gel (100–200 mesh) was used for column chromatography. Cyclopropanes 4a – p were prepared as per our reported procedure, and among them 4a – g and 4i – n are known compounds. , …”

Ammonia surrogates in the synthesis of primary amines

“…Recent advancements in this field have focused on finding alternative methods to induce the cation formation. 77 In this regard, one noteworthy approach is the electrochemical activation of tertiary or benzylic C–H bonds.…”

The Cloke–Wilson rearrangement of aroyl-substituted donor–acceptor cylopropanes containing arylethyl donors

“…8 It should be noted that γ-butyrolactones are structural subunits in a large number of natural products 9 and medicinally important compounds 10 and hence several methods have been reported for their synthesis. 11…”