Kinetic resolution of primary amines via enantioselective N-acylation with acyl chlorides in the presence of supramolecular cyclodextrin nanocapsules

Control of Guest Inclusion and Chiral Recognition Ability of 6‐O‐Modified β‐Cyclodextrins in Organic Solvents by Aromatic Substituents at the 2‐O Position

“…In particular, host 1 c exhibited a high binding selectivity for (S)-2 a, which is close to the chiral selectivity of supramolecular TBDMS-β-CD dimer. [11] Additionally, in the NOESY spectra of the inclusion complexes of 1c and (R)-and (S)-2a ( Figure S25), the naphthalene protons of (S)-2 a exhibited cross peaks towards the H 5 protons of 1 c, while such signals were faintly observed with (R)-2 a. This suggests that the naphthalene ring of (S)-2 a is enclosed much deeper in the cavity of c. Hence, the chiral selectivity can be explained in terms of the difference in the penetration of (R)and (S)-2 a into the CD cavity.…”

“…This idea was then extended to the design of a supramolecular dimer of TIPS-β-CD that shows excellent chiral recognition of an aromatic amine in cyclohexane. [10][11] The crystal structure of the host-guest complex of the supramolecular TIPS-β-CD dimer and pyrene suggests that strong π-π interactions between pyrene and benzene solvent molecules inside the cavity of TIPS-β-CD improve the overall stability of the complex. [9] We hypothesized that a 6-O-modified CD with an appropriate aromatic substituent at the 2-O position can interact with aromatic guests through the π-π interactions and exhibit a high inclusion ability for aromatic guests in organic solvents.…”

Cyclodextrins in Asymmetric and Stereospecific Synthesis

“…Thus, one of the enantiomeric forms of the epoxide in the β-CD cavity, due to its favorable geometry, is captured selectively by the external amine, and the phenomenon of dynamic resolution takes place under the reaction conditions. Later, Asahara et al [61] also demonstrated that the kinetic resolution of primary amines is possible through enantioselective N-acylation with acyl chlorides with selective sequestration of one enantiomer within the cyclodextrin cavity in nonpolar solvents.…”

Controlling the polymerization of coniferyl alcohol with cyclodextrins

“…The internal cavity volume of α, β and γCD directly influences the size of the guest a CD molecule can accommodate. 3 Because of these properties, CDs are used to enhance the solubility and bioavailability of numerous Notably, in enantioselective synthesis, CDs or their derivatized forms have been shown to increase the enantiopure production of β-amino alcohols 5 and to facilitate the enantioselective N-acylation of primary amines 6 . CDs have been also shown to significantly improve enantiomeric excess in enzyme-catalysed reactions, such as the peroxidase catalysed synthesis of binaphthyl derivatives from naphtols and the esterase catalysed synthesis of the S-enantiomer of the anti-inflammatory drug naproxen.…”