Enantioselective Steglich Rearrangement of Oxindole Derivatives by Easily Accessible Chiral N,N-4-(Dimethylamino)pyridine Derivatives

Abstract

Chiral N,N-4-(dimethylamino)pyridine (DMAP) derivatives, which can be readily prepared by the Ugi multicomponent reaction in a one-pot manner, have been efficiently applied to the enantioselective Steglich rearrangement of oxindole derivatives to give the desired products bearing a quaternary carbon center in high yield (>98% yield) and with high enantioselectivity (up to 99:1 er).

Enantiodivergent Steglich rearrangement of O-carboxylazlactones catalyzed by a chirality switchable helicene containing a 4-aminopyridine unit

“…13 Recently, easily accessible C-3 functionalized DAMPs were described by Poisson, 14 Mandai and Suga. 15 In addition, chiral tetrahydropyrimidine-based isothioureas and chiral N -heterocyclic carbenes ( i.e. NHC) utilized by Smith, 16 chiral ammonium betaines employed by Ooi, 17 and chiral bicyclic imidazoles designed by Zhang 18 were developed with better enantiocontrol or broader substrate scope.…”

Enantioselective acyl transfer catalysis by a combination of common catalytic motifs and electrostatic interactions

“…According to our continuous efforts for the development of chiral nucleophilic catalysts 17 18 19 to design an efficient and highly enantioselective acyl transfer catalyst that can be prepared in significant quantities without the need for expensive and/or specialized techniques, we envisioned chiral DMAP derivatives that might contain a binaphthyl unit at C4 position of a pyridine ring ( Fig. 2 ).…”

“…With a collection of possible catalysts in hand, we chose Steglich rearrangement 1 15 19 34 42 43 of oxindole derivative 9a (Design option 1, Fig. 2 ) as the model transformation for identifying the optimal promoter molecule.…”

“…1b ) 9 . A similar approach but involving the C3 site of the heterocyclic ring, has been extensively examined 11 12 13 14 15 16 17 18 19 . Nonetheless, reactivity levels were again generally reduced, probably as a result of hampering of proper electron donation by the amino substituent, which raises the energy of the critical pyridinium ion intermediates (cf.…”

Kinetic Resolution of Tertiary Benzyl Alcohols via Palladium/Chiral Norbornene Cooperative Catalysis

“…Since chiral tertiary benzyl alcohols are important structural motifs prevalent in pharmaceuticals (Figure 1 A), considerable efforts have been devoted to the challenging KR of these tertiary alcohols so far, culminating in the development of a few elegant strategies (Figure 1 B). [2–13] Pioneered by Miller [2] and later on by Zhao, [3] Smith [4] and Suga, [5] the nonenzymatic [6] acylative KRs using pentapeptide or chiral Lewis base catalyst were developed. List and Yang successively developed efficient KR strategies based on chiral phosphoric acid‐catalyzed (trans)acetalization, [7] transesterification [8] or condensation [9] .…”