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Experimental and computed nuclear magnetic resonance data and an iterative synthetic strategy have revealed the correct structures of the baulamycins, potentially important antimicrobial compounds, allowing them to be chemically synthesized.

Automated organic synthesis is often limited to making simple molecules, requiring a small number of synthetic steps, because of the complexity and variety of organic molecules. Now, a robotic platform has been instructed to build complex structures, such as the core fragment of (+)-kalkitoxin, in a stereochemically controlled and iterative manner.

Metal-free borylation of C(sp³)–H bonds by violet-light-induced hydrogen atom transfer is reported, demonstrating high selectivity for the substitution of methyl C–H bonds over other weaker C–H bonds.

Boronic esters are versatile intermediates that readily accept nucleophiles and then undergo 1,2-migration, expelling a neighbouring leaving group. Such reactivity enables carbon chains to be grown one atom at a time with high stereocontrol. This Review examines the fundamentals of lithiation–borylation methodology and its application to natural product synthesis.

A method based on boron-mediated assembly is described for the synthesis of tetrasubstituted alkenes, molecules with four substituents around the central C=C bond, with complete control over the double-bond geometry.

Widely used palladium-mediated cross-couplings typically operate via a handful of fundamental reaction steps. Now, the reactivity between palladium and C–C σ-bonds has been described. This carbopalladation enables the coupling of organoboronic esters and aryl triflates across a C–C σ-bond of a bicyclo[1.1.0]butane to form disastereomerically pure trisubstituted cyclobutanes.

The structures of 1,5-polyol-containing polyketide-derived natural products are notoriously difficult to determine using spectroscopic techniques due to spectral overlap and chemical shift degeneracy. Now, a blueprint for the structure determination of this class of natural products is reported, combining ultra-high-resolution NMR spectroscopy and synthesis to unveil the correct structure of caylobolide A.

A remarkable reaction that reverses the chemical behaviour of molecules known as 1,3-diketones allows a new strategy that could be used to prepare a range of potentially useful, naturally occurring compounds. See Letter p.86

New methodology that couples together carbonyl compounds with boronic acids shows much promise for synthesis owing to ease of access of the building blocks, functional group tolerance and broad scope of the reaction.

A concise new synthesis of the most complex of the prostaglandins—diverse hormone-like chemical messengers—should make existing prostaglandin-based drugs cheaper and also facilitate other related syntheses.

A new method to convert secondary alcohols in their single mirror image form into tertiary alcohols has been developed. Starting from a single enantiomer of the secondary alcohol, either mirror image form of the tertiary alcohol can be made with very high levels of stereocontrol. A broad range of tertiary alcohols can now be easily made by this method with very high levels of selectivity.

Polyketide natural products often contain common repeat motifs that are synthesized using iterative processes. Now a masked 1,3-diol motif, generated by a two-step process based on boronic ester homologation, has enabled the efficient iterative synthesis of polyacetates, including bahamaolide A. In addition to oxidation, the 1,3-polyboronic esters were shown to undergo various stereospecific transformations.

The iterative, reagent-controlled homologation of a boronic ester is used to create an ‘assembly line’ capable of synthesizing organic molecules that contain ten contiguous, stereochemically defined methyl groups and which have different shapes depending on the stereochemistry of those groups.

Coupling of carbamates with boronic esters followed by protodeboronation creates a new carbon–carbon bond, leaving behind no trace of the functional groups used to create it. Now, methodology for the protodeboronation of alkyl pinacol boronic esters has been developed and an iterative lithiation–borylation–protodeboronation strategy used in a 14-step stereocontrolled synthesis of hydroxyphthioceranic acid.

A general and broad-ranging stereospecific coupling of secondary and tertiary boronic esters with electron-rich aromatics is reported. The reaction involves initial formation of a boronate complex followed by activation of the electron-rich aromatic moiety by an electrophile, which triggers a stereospecific 1,2-migration and subsequent elimination/re-aromatization.

Polypropionates can be grown — one carbon atom at a time — using the iterative homologation of boronic esters. This assembly line strategy was enabled through the use of enantioenriched lithiated α-chlorosilanes as masked carbinol units. Polypropionates were obtained in a fully stereocontrolled manner, including the stereochemically challenging anti–anti isomers.

Even- and odd-numbered homologues of some hydrocarbons are known to exhibit different trends in solid-state properties. Now, experimental and computational investigations on a homologous series of a stereochemically well-defined hydrocarbon have revealed an odd–even effect in conformational behaviour in solution that is caused by a single gauche interaction.