Chiral Lewis Base Activation of Acyl and Related Donors in Enantioselective Transformations ( n ?→?π ^* )

Development of a Chiral DMAP Catalyst for the Dynamic Kinetic Resolution of Azole Hemiaminals

“…Importantly, enantioselectivity of the DKR with preformed isobutyric anhydride and with the in situ generated mixed anhydride was almost identical (entry 1, Table 2, and entry 1, Table 3). Propionic acid yielded hemiaminal ester (R)-12r with high enantioselectivity (entry 2, Table 3); however, decreased levels of enantiocontrol were observed using other carboxylic acids such as cyclopentanecarboxylic acid (entry 3), phenylacetic acid (entry 4), N-Bocglycine (entry 5), and N-Boc-sarcosine (entry 6).…”

“…Chiral N , N -dimethylaminopyridine (DMAP) catalysts have found wide application in asymmetric synthesis. , Following seminal contributions by Vedejs and Fu, , a variety of chiral DMAP derivatives have been developed for a range of enantioselective acyl-transfer reactions. − The development of new chiral DMAP catalysts often has relied on an empirical approach involving the preparation and testing of a large number of structural analogues. For example, the development of a catalyst for the enantioselective Steglich rearrangement of oxindoles has required the synthesis of a small library of chiral DMAP analogues using the multicomponent Ugi reaction. , A complementary approach to the de novo synthesis of chiral pyridines is structural modification of already-established DMAP catalysts to enable new synthetic applications .…”

Kinetic resolution of racemic tertiary allylic alcohols through SN2′ reaction using a chiral bisphosphoric acid/silver(i) salt co-catalyst system

“…2 Another potential method is the catalytic kinetic resolution (KR) 3 of racemic tertiary alcohols. In contrast to the catalytic KR of racemic secondary alcohols, 4 reliable methods for the non-enzymatic KR of tertiary alcohols remain few. 5–9 Several groups have reported the use of chiral Lewis base (nucleophilic) catalysts 6 and chiral transition metal catalysts.…”

Acylative Kinetic Resolution of Alcohols Using a Recyclable Polymer-Supported Isothiourea Catalyst in Batch and Flow

“…Of these methods, the catalytic acylative KR of alcohols is a powerful method to prepare highly enantioenriched alcohols (Scheme ). Chiral Lewis base catalysis is most commonly applied for this transformation, with a range of excellent catalysts reported for the KR of many classes of secondary alcohols. A current limitation of this method is that the Lewis base catalyst is rarely recovered from the reaction.…”