We report here a highly selective copper(II)-catalysed asymmetric Friedel–Crafts conjugate addition/enantioselective protonation, which owes to a careful positioning of a bipyridine ligand within a DNA framework.

α,β-Unsaturated acylimidazoles have been used in a plethora of enantioselective transformations over the years and have unsurprisingly become privileged building blocks for asymmetric catalysis. Interestingly however, their use in asymmetric biohybrid catalysis as bidentate substrates able to interact with artificial metalloenzymes has only recently emerged, expanding considerably in the last few years. Easy to prepare and to posttransform, α,β-unsaturated acylimidazoles appear as leading synthons for the asymmetric construction of CÀ C and CÀ O bonds. This Minireview highlights the current and increasing interest of these key building blocks in the context of asymmetric biohybrid catalysis with the aim to stimulate further research into their still unexploited potential. The use of these α,β-unsaturated acylimidazoles in metal-catalyzed and organocatalyzed transformations will be covered in a back-to-back Minireview

Biosynthetic considerations inspired us to harness the templating properties offered by DNA to promote a [2+2] photoinduced cycloaddition. The method was developed based on the dimerization of (E)-aplysinopsin, which was previously shown to be unproductive in solution. In sharp contrast, exposure of this tryptophan-derived olefin to light in the presence of salmon testes DNA (st-DNA) reproducibly afforded the corresponding homo-dimerized spiro-fused cyclobutane in excellent yields. DNA provides unique templating interactions enabling a singular mimic of the solid-state aggregation necessary for the [2+2] photocycloaddition to occur. This method was ultimately used to promote the prerequisite dimerizations leading to both dictazole B and tubastrindole B, thus constituting the first example of a DNA-mediated transformation to be applied to the total synthesis of a natural product.

While artificial cyclases hold great promise in chemical synthesis, this work presents the first example of a DNA‐catalyzed inverse electron‐demand hetero‐Diels–Alder (IEDHDA) between dihydrofuran and various α,β‐unsaturated acyl imidazoles. The resulting fused bicyclic O,O‐acetals containing three contiguous stereogenic centers are obtained in high yields (up to 99 %) and excellent diastereo‐ (up to >99:1 dr) and enantioselectivities (up to 95 % ee) using a low catalyst loading. Most importantly, these results show that the concept of DNA‐based asymmetric catalysis can be expanded to new synthetic transformations offering an efficient, sustainable, and highly selective tool for the construction of chiral building blocks.

No abstract

Biosynthetic considerations inspired us to harness the template properties offered by DNA to promote a [2+2] photo-induced cycloaddition. The method was developed based on the dimerization of (E)-aplysinopsin, which was previously shown to be unproductive in solution. In sharp contrast, exposure of this tryptophan-derived olefin to light in the presence of salmon testes DNA (st-DNA) reproducibly afforded the corresponding homo-dimerized spiro-fused cyclobutane in excellent yields. DNA provides unique templating interactions enabling a singular mimic of the solid-state aggregation necessary for the [2+2] photo-cycloaddition to occur. This method was ultimately used to promote the prerequisite dimerizations leading to both dictazole B and tubastrindole B, thus constituting the first example of a DNA-mediated transformation to be applied to the total synthesis of a natural product.