Anchorene is a carotenoid-derived regulatory metabolite required for anchor root formation in .

Anchor roots (ANRs) arise at the root-shoot junction and are the least investigated type of root. Here, we show that ANRs originate from pericycle cells in an auxin-dependent manner and a carotenogenic signal to emerge. By screening known and assumed carotenoid derivatives, we identified anchorene, a presumed carotenoid-derived dialdehyde (diapocarotenoid), as the specific signal needed for ANR formation.

A combined continuous microflow photochemistry and asymmetric organocatalysis approach for the enantioselective synthesis of tetrahydroquinolines.

A continuous-flow asymmetric organocatalytic photocyclization-transfer hydrogenation cascade reaction has been developed. The new protocol allows the synthesis of tetrahydroquinolines from readily available 2-aminochalcones using a combination of photochemistry and asymmetric Brønsted acid catalysis. The photocylization and subsequent reduction was performed with catalytic amount of chiral BINOL derived phosphoric acid diester and Hantzsch dihydropyridine as hydrogen source providing the desired products in good yields and with excellent enantioselectivities.

Shedding light on Brønsted acid catalysis--a photocyclization-reduction reaction for the asymmetric synthesis of tetrahydroquinolines from aminochalcones in batch and flow.

A new asymmetric photocyclization-reduction cascade employing readily available aminochalcones has been developed. The reaction sequence has been achieved by unifying photochemistry and asymmetric Brønsted acid catalysis and involves photocyclization followed by Brønsted acid catalyzed enantioselective hydrogenation in batch and flow.

Shedding light on organocatalysis-light-assisted asymmetric ion-pair catalysis for the enantioselective hydrogenation of pyrylium ions.

A new light-driven asymmetric ion-pair catalysis procedure for the metal-free enantioselective hydrogenation of in situ generated pyrylium ions from readily available chalcones was developed (see scheme). The photo-assisted Brønsted acid catalyzed procedure has broad scope and allows, for the first time, access to valuable 4H-chromenes in good yields and with excellent enantioselectivities.

Continuous-flow catalytic asymmetric hydrogenations: Reaction optimization using FTIR inline analysis.

The asymmetric organocatalytic hydrogenation of benzoxazines, quinolines, quinoxalines and 3H-indoles in continuous-flow microreactors has been developed. Reaction monitoring was achieved by using an inline ReactIR flow cell, which allows fast and convenient optimization of reaction parameters. The reductions proceeded well, and the desired products were isolated in high yields and with excellent enantioselectivities.

Unifying metal- and organocatalysis for asymmetric oxidative iminium activation: a relay catalytic system enabling the combined allylic oxidation of alcohols and prolinol ether catalyzed iminium reactions.

A multicatalytic system consisting of tetrapropylammonium perruthenate/N-methylmorpholine N-oxide (TPAP/NMO) as oxidant, and diarylprolinol TMS-ether as chiral amine catalyst, has been developed and applied in the efficient construction of valuable chiral molecules. The one-pot domino reactions elaborated in the present study are based on the in situ generation of α,β-unsaturated aldehydes from allylic alcohols and their subsequent use in various asymmetric transformations (e.g.

Asymmetric oxidative Lewis base catalysis-unifying iminium and enamine organocatalysis with oxidations.

Enantioselective oxidative domino reactions of allylic alcohols to functionalized aldehydes have been developed. The one pot domino oxidation-iminium activation represents a convenient strategy for the enantioselective addition of malonates to allylic alcohols and the asymmetric formation of formyl cyclopropanes.

Continuous-flow hydration-condensation reaction: Synthesis of α,β-unsaturated ketones from alkynes and aldehydes by using a heterogeneous solid acid catalyst.

A simple, practical and efficient continuous-flow hydration-condensation protocol was developed for the synthesis of α,β-unsaturated ketones starting from alkynes and aldehydes by employing a heterogeneous catalyst in a flow microwave. The procedure presents a straightforward and convenient access to valuable differently substituted chalcones and can be applied on multigram scale.

Enantioselective organocatalytic synthesis of quaternary α-amino acids bearing a CF3 moiety.

A highly enantioselective Friedel-Crafts reaction catalyzed by a chiral phosphoric acid was developed. N-Boc-protected ethyl trifluoropyruvate imine was activated by 6 mol % of catalyst and reacted with a wide variety of indole derivatives to afford quaternary α-amino acids in excellent yields (up to 99%) and high enantioselectivities (up to 98:2 er).

Two polymorphs of 4-propyl-3,4-dihydro-2H-naphtho[1,2-b]pyran-5,6-dione.

Two polymorphs of the title compound, C(16)H(16)O(3), have been obtained from the same solution. One polymorph, (I(m)), crystallizes in the monoclinic space group P2(1), while the other, (I(o)), crystallizes in the orthorhombic space group P2(1)2(1)2(1). The cell constants of the two polymorphs are surprisingly similar.

An enantioselective chiral Brønsted acid catalyzed imino-azaenamine reaction.

The enantioselective Brønsted acid catalyzed addition of methyleneaminopyrrolidine to N-Boc imines has been achieved in the presence of chiral phosphoric acids derived from 3,3'-di(phenanthryl)-H8-BINOL. The corresponding aminohydrazones have been isolated in good yields with enantiomeric excesses up to 90%. [reaction: see text]

Enantioselective Brønsted acid catalyzed transfer hydrogenation: organocatalytic reduction of imines.

The first enantioselective Brønsted acid catalyzed reduction of imines has been developed. This new organocatalytic transfer hydrogenation of ketimines with Hantzsch dihydropyridine as the hydrogen source offers a mild method to various chiral amines with high enantioselectivity. The stereochemistry of the chiral amines can be rationalized by a stereochemical model derived from an X-ray crystal structure of a chiral BINOL phosphate catalyst.