Absolute Stereochemical Determination of Asymmetric Sulfoxides via Central to Axial Induction of Chirality

The absolute configuration of chiral sulfoxides is determined by means of host–guest complexation that leads to the induction of axial chirality in an achiral host. The central to axial induction of helicity is rationalized by a simple recognition of the relative length and size of the substituents attached to the S-center. This technique is used to determine the absolute configuration of chiral sulfoxides, requiring micrograms of sample, without the need for prefunctionalization

Absolute Stereochemical Determination of Asymmetric Sulfoxides via Central to Axial Induction of Chirality

The absolute configuration of chiral sulfoxides is determined by means of host–guest complexation that leads to the induction of axial chirality in an achiral host. The central to axial induction of helicity is rationalized by a simple recognition of the relative length and size of the substituents attached to the S-center. This technique is used to determine the absolute configuration of chiral sulfoxides, requiring micrograms of sample, without the need for prefunctionalization

Point-to-Axial Chirality TransferA New Probe for “Sensing” the Absolute Configurations of Monoamines

A host molecule, capable of freely adopting <i>P</i> or <i>M</i> helicity, is described for molecular recognition and chirality sensing. The host, consisting of a biphenol core, binds chiral amines via hydrogen-bonding interactions. The diastereomeric complex will favor either <i>P</i> or <i>M</i> helicity as a result of minimizing steric interactions of the guest molecule with the binding cavity of the host, resulting in a detectable exciton-coupled circular dichroic spectrum. A working model is proposed that enables non-empirical prediction of the chirality of the bound amine

Computationally Aided Absolute Stereochemical Determination of Enantioenriched Amines

A simple and efficient protocol for sensing the absolute stereochemistry and enantiomeric excess of chiral monoamines is reported. Preparation of the sample requires a single-step reaction of the 1,1′-(bromomethylene)­dinaphthalene (BDN) with the chiral amine. Analysis of the exciton coupled circular dichroism generated from the BDN-derivatized chiral amine sample, along with comparison to conformational analysis performed computationally, yields the absolute stereochemistry of the parent chiral monoamine

Mechanistically Inspired Route toward Hexahydro‑2<i>H</i>‑chromenes via Consecutive [4 + 2] Cycloadditions

Utilizing two robust C–C bond-forming reactions, the Baylis–Hillman reaction and the Diels–Alder reaction, we report a highly enantio-, regio-, and diastereoselective synthesis of hexahydro-2<i>H</i>-chromenes via two sequential [4 + 2] cycloadditions. These tandem and formal cycloadditions have also been performed as a “one-pot” sequence to access the corresponding heterocycles constituting up to five contiguous stereocenters in excellent yields and stereoselectivity