Regio- and stereoselective synthesis of γ-alkylidenebutenolides by cyclization of dilithiated 1,3-dicarbonyl compounds with N,N’-dimethoxy-N,N’-dimethylethanediamide was written by Langer, Peter;Stoll, Martin. And the article was included in Angewandte Chemie, International Edition in 1999.SDS of cas: 106675-70-1 This article mentions the following:
In most cases the title reactions gave (E)-alkylidenebutenolides [I; R1 = H, Me; R2 = H, Me, Et; R3 = OEt, OCMe3, Me, NEt2, Ph; R2R3 = CH2CH2O, (CH2)4, CH2CHMeO, etc.]. In two cases the Z isomers predominated. In the experiment, the researchers used many compounds, for example, N1,N2-Dimethoxy-N1,N2-dimethyloxalamide (cas: 106675-70-1SDS of cas: 106675-70-1).
N1,N2-Dimethoxy-N1,N2-dimethyloxalamide (cas: 106675-70-1) belongs to amides. Amides are pervasive in nature and technology. Proteins and important plastics like Nylons, Aramid, Twaron, and Kevlar are polymers whose units are connected by amide groups (polyamides); these linkages are easily formed, confer structural rigidity, and resist hydrolysis. In simple aromatic amides, fragmentation occurs on both sides of the carbonyl group. If a hydrogen is available in N-substituted aromatic amides, it tends to migrate and form an aromatic amine and the loss of a ketene.SDS of cas: 106675-70-1
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics