Applications of Claisen condensations in total synthesis of natural products. An old reaction, a new perspective

Early Process Development of CH7057288, a Benzofuran-Containing Selective NTRK Inhibitor

“…Therefore, our focus quickly turned to using a fully protected amino functional group, and an amidine type protecting group was chosen . Treating methyl ester 21 with N,N -dimethylformamide dimethyl acetal (DMF-DMA) in toluene by heating to 75 °C produced amidine 34 , and Claisen reaction of 34 with tert -butyl acetate ( tert -BuOAc) using LiHMDS in THF was performed to give β-keto ester 35 (Scheme ). A subsequent S N Ar reaction of 35 with aryl fluoride 29 using Cs 2 CO 3 in NMP provided α-aryl-β-keto ester 28 .…”

Organocatalytic Asymmetric Peroxidation of γ,δ-Unsaturated β-Keto Esters—A Novel Route to Chiral Cycloperoxides

“…OMe Ph β-Keto esters constitute highly versatile building blocks in organic synthesis which can be readily modified through a wide variety of transformations [36][37][38][39][40][41][42]. To date, β-keto esters have been mostly employed as nucleophiles in organocatalysed reactions [43].…”

Continuous‐Flow Synthesis of β‐Ketoesters and Successive Reactions in One‐Flow using Heterogeneous Catalysis

“…[8][9][10] β-Ketoesters are highly reactive intermediates in organic synthesis and they are widely used for the construction of heterocyclic structures [11,12] that make up bioactive molecules, [13] drug molecules, [14][15][16][17][18][19] and natural products. [20,21] Numerous synthetic strategies through CÀ C bond-formation processes have been explored, including Claisen condensation (Figure 1(a)) [22][23][24][25][26][27] and acylation; [28] however, the low pK a value of the proton at the α-position of β-ketoesters or high coordination abilities of their 1,3-dicarbonyl structures require the use of stoichiometric amounts of acids or strong bases in most cases.…”