: The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

Ab initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields

Complete Field Guide to Asymmetric BINOL-Phosphate Derived Brønsted Acid and Metal Catalysis: History and Classification by Mode of Activation; Brønsted Acidity, Hydrogen Bonding, Ion Pairing, and Metal Phosphates

The present review is devoted to summarizing the recent advances (2015-2017) in the field of metal-catalysed group-directed C-H functionalisation In order to clearly showcase the molecular diversity that can now be accessed by means of directed C-H functionalisation, the whole is organized following the directing groups installed on a substrate Its aim is to be a comprehensive reference work, where a specific directing group can be easily found, together with the transformations which have been carried out with it Hence, the primary format of this review is schemes accompanied with a concise explanatory text, in which the directing groups are ordered in sections according to their chemical structure The schemes feature typical substrates used, the products obtained as well as the required reaction conditions Importantly, each example is commented on with respect to the most important positive features and drawbacks, on aspects such as selectivity, substrate scope, reaction conditions, directing group removal, and greenness The targeted readership are both experts in the field of C-H functionalisation chemistry (to provide a comprehensive overview of the progress made in the last years) and, even more so, all organic chemists who want to introduce the C-H functionalisation way of thinking for a design of straightforward, efficient and step-economic synthetic routes towards molecules of interest to them Accordingly, this review should be of particular interest also for scientists from industrial R&D sector Hence, the overall goal of this review is to promote the application of C-H functionalisation reactions outside the research groups dedicated to method development and establishing it as a valuable reaction archetype in contemporary R&D, comparable to the role cross-coupling reactions play to date

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A comprehensive overview of directing groups applied in metal-catalysed C-H functionalisation chemistry.

Catalytic C-C bond-forming multi-component cascade or domino reactions: pushing the boundaries of complexity in asymmetric organocatalysis.

Recent Advances of Catalytic Asymmetric 1,3-Dipolar Cycloadditions

The asymmetric organocatalysis is definitely one of the most powerful and versatile tools for the rapid construction of various spirocyclic oxindoles. In the past few years, a number of successful strategies based on organocatalysis have been developed for the construction of 3,3′-spirocyclic oxindoles in high yields and excellent enantioselectivities under mild conditions. In this review, recent advances in this area are summarized and classified according to the spiro ring fused at the 3-position of the oxindole core.

Recent Advances in Asymmetric Organocatalytic Construction of 3,3′-Spirocyclic Oxindoles

This review highlights a number of additives that can be used to make asymmetric reactions perfect. Without changing other reaction conditions, simply adding additives can lead to improved asymmetric catalysis, such as reduced reaction time, improved yield, or/and increased selectivity.

Additive Effects on Asymmetric Catalysis

This review summarizes the recent advances in the field of asymmetric dearomatization of phenols and their applications in the total synthesis of some complex natural products. The dearomatization discussed here includes metal catalysed direct dearomatization, organocatalytic dearomatization and hypervalent iodine mediated dearomatization.

Asymmetric dearomatization of phenols

A rapid and efficient organocatalytic cascade sequence for the direct construction of spirocyclopentane bioxindoles has been carried out by using a chiral squaramide catalyst in the presence of a base. This process constitutes a powerful approach to the preparation of biologically important bispirooxindoles in high enantioselectivities (see scheme).

An organocatalytic cascade strategy for the enantioselective construction of spirocyclopentane bioxindoles containing three contiguous stereocenters and two spiro quaternary centers.

Highly congested vicinal all-carbon quaternary stereocenters were generated via catalytic asymmetric alkylation reaction of 3-bromooxindoles with 3-substituted indoles. These catalytic reactions proceeded in excellent yields with a broad scope on either reaction partner, and with outstanding diastereo- and enantiocontrol. The newly developed method led to the total synthesis of (+)-perophoramidine in a highly efficient manner.

Construction of Vicinal All-Carbon Quaternary Stereocenters by Catalytic Asymmetric Alkylation Reaction of 3-Bromooxindoles with 3-Substituted Indoles: Total Synthesis of (+)-Perophoramidine

Liang Hong

Papers

Recent Advances in Asymmetric Organocatalytic Construction of 3,3′-Spirocyclic Oxindoles

Additive Effects on Asymmetric Catalysis

Asymmetric dearomatization of phenols

An organocatalytic cascade strategy for the enantioselective construction of spirocyclopentane bioxindoles containing three contiguous stereocenters and two spiro quaternary centers.

Construction of Vicinal All-Carbon Quaternary Stereocenters by Catalytic Asymmetric Alkylation Reaction of 3-Bromooxindoles with 3-Substituted Indoles: Total Synthesis of (+)-Perophoramidine