Applications of alkyl orthoesters as valuable substrates in organic transformations, focusing on reaction media

Abstract

In this review we focus on applications of alkyl orthoesters as valuable and efficient substrates to perform various classes of two-component and multi-component organic reactions.

New Advances in the Synthesis of Emerging Cyclic Amidrazones to Foster Bioisosterism of Azaheterocycles

“…In view of promoting efficiently the formation of the cyclic amidrazone, the next step of the sequence consists in a cyclisation of the aminohydrazine salt 3 to the cyclic amidrazone 4 a (Scheme 1). At that stage, we turned our attention on reactions from the literature allowing the preparation of cyclic amidine motifs starting from simple diamines in presence of various cyclization reagents including imidoesters, [11] imidazolines, [12] thioamides, [13] orthoesters, [14] carboxylic acids, [15] aldehydes in situ combined with oxidants, [16] as well as catalystor acid-based processes with nitrile or nitroalkanes. [17] Based on these considerations, we first explored the formation of cyclic amidrazones 4 a by screening several cyclization partners (Table 1).…”

Design, synthesis and molecular docking of new fused 1H-pyrroles, pyrrolo[3,2-d]pyrimidines and pyrrolo[3,2-e][1, 4]diazepine derivatives as potent EGFR/CDK2 inhibitors

“…Moreover, several studies reported the use of triethyl orthoformate to produce cyclized derivatives 64 . The tricyclic pyrrolo[3,2- d ]pyrimidine derivatives 9a–c were achieved by refluxing compounds 5a–c with excess triethyl orthoformate ( Scheme 3 ).…”

Iron‐Catalyzed N, N‐formyl Ethylation of Amines

“…Moreover, many strategies have been developed for the synthesis of N ‐formyl amines using orthoesters [19–23] . Notably, alkyl orthoesters are useful and efficient starting materials for two‐component and multi‐component organic reactions [24] . They can also be obtained from mixed anhydrides include formic acid‐EDAC, [25] formic acid‐DCC, [26] acetic formic anhydride, [27] and formyl pivaloyl anhydride [28] .…”

“…[19][20][21][22][23] Notably, alkyl orthoesters are useful and efficient starting materials for two-component and multi-component organic reactions. [24] They can also be obtained from mixed anhydrides include formic acid-EDAC, [25] formic acid-DCC, [26] acetic formic anhydride, [27] and formyl pivaloyl anhydride. [28] Formylation with formates consisting of 2,2,2-trifluoroethyl formate, [29] cyanomethyl formate, [30] and pentafluorophenyl formate [31] have been reported in the literature.…”