Enantioselective Domino Research Articles

Enantioselective domino reaction of CO2, amines and allyl chlorides under iridium catalysis: formation of allyl carbamates

The enantioselective domino reaction between CO2 (1 atm), amines and linear allyl chlorides in the presence of an iridium complex, DABCO and toluene at 15 °C was realized, which gave branched allyl carbamates in acceptable to high yields with up to excellent regioselectivity (99/1) and 94% ee. This is the first example of the synthesis of chiral allyl carbamates through catalytic domino reactions using CO2.

α,β‐Unsaturated Acyl Cyanides as New Bis‐Electrophiles for Enantioselective Organocatalyzed Formal [3+3]Spiroannulation

α,β-Unsaturated acyl cyanides are key bis-electrophile substrates for successful domino enantioselective organocatalyzed Michael-intramolecular acylation domino sequences. This new reactivity has been applied to the synthesis of enantioenriched azaspiro[4,5]decanone ring systems by a formal [3+3]spiroannulation, constituting a rare example of synthesis of glutarimides in an optically active form.

Highly enantioselective catalytic domino reaction: Synthesis of (R)-2-phenyl-2H-thiochromene-3-carbaldehyde in supercritical carbon dioxide

Highly enantioselective catalytic domino reaction: Synthesis of (R)-2-phenyl-2H-thiochromene-3-carbaldehyde in supercritical carbon dioxide

Enantioselective Squaramide‐Catalysed Domino Mannich–Cyclization Reaction of Isatin Imines

AbstractAn enantioselective domino reaction of 4‐bromo‐3‐oxobutanoates with isatin‐derived ketimines was developed to construct 3‐amino‐2‐oxindoles with a quaternary stereocentre. In the presence of 1 mol‐% of a bifunctional squaramide organocatalyst, the desired products were achieved in high yields (90–97 %) and with excellent enantioselectivities (92–99 % ee).

ChemInform Abstract: Activation of 1,2‐ and 1,3‐Ketoamides with Thiourea Organocatalyst for the Enantioselective Domino Synthesis of Functionalized Cyclohexanes.

AbstractThe diketoacid substrates are activated by BTU to react with nitroolefins or acrolein.

ChemInform Abstract: Enantioselective Rh‐Catalyzed Domino Transformations of Alkynylcyclohexadienones with Organoboron Reagents.

AbstractTitle reactions proceed with moderate to good enantioselectivities.

Activation of 1,2- and 1,3-Ketoamides with Thiourea Organocatalyst for the Enantioselective Domino Synthesis of Functionalized Cyclohexanes

Several reactive sites of 1,2- and 1,3-ketoamides were successively exploited in two complementary domino transformations for the synthesis of polysubstituted monocyclic or bridged bicyclic cyclohexanes, with the creation of up to six stereogenic centers. In both cases, a chiral bifunctional thiourea organocatalyst allowed efficient control of chirality in the final carbocycle.

Highly Diastereo- and Enantioselective Organocatalytic Domino Michael/Aldol Reaction of Acyclic 3-Halogeno-1,2-Diones to α,β-Unsaturated Aldehydes

The first organocatalytic diastereo- and enantioselective domino Michael/aldol reaction of 3-halogeno-1,2-diones to α,β-unsaturated aldehydes has been achieved. This transformation tolerates a large variety of electronically different substituents on both reactive partners and allows the synthesis of challenging cyclopentanone derivatives with four contiguous stereogenic centers in excellent diastereoselectivities (>20:1 dr) as well as good yields (69-97%), and enantioselectivities (up to 94% ee).

Enantioselective Rh-Catalyzed Domino Transformations of Alkynylcyclohexadienones with Organoboron Reagents

A new enantioselective rhodium-catalyzed domino reaction is described that gives access to fused heterocycles by desymmetrization of alkyne-tethered cyclohexadienones. Two new C-C bonds and two stereocenters are formed in one step with good enantioselectivity. In contrast to prior reports, it was found that a vinylidene is not involved in the product formation but that syn-addition of the rhodium-aryl species onto the alkyne takes place.

Chiral Aryl–Copper(III) Electrophiles: New Opportunities in Catalytic Enantioselective Arylations and Domino Processes

"Chiral aryl cation" equivalents: The combination of diaryliodonium salts and catalytic amounts of chiral copper complexes provides facile access to "chiral aryl cation" synthons. These reagents offer new possibilities for asymmetric arylation reactions that initiate further domino processes.

ChemInform Abstract: Synthesis of 2,3,5,6‐Tetrahydro‐1‐alkyl/aryl‐1H‐benzo[f]chromen‐3‐ol Derivatives from β‐Tetralones and α,β‐Unsaturated Aldehydes.

AbstractThe organocatalytic enantioselective domino Michael‐hemiacetalization of β‐tetralones (I) and α,β‐unsaturated aldehydes (II) is reported.

ChemInform Abstract: Enantioselective Synthesis of 2‐Substituted‐1,5‐benzodiazepines Through Domino Reaction of o‐Phenylenediamine and Chalcone Derivatives.

Chiral 2-substituted-1,5-benzodiazepine derivatives were synthesized for the first time from an enantioselective domino reaction involving o-phenylenediamine and 2′-hydroxychalcones. The titanium complex formed from chiral ligand 1a derived from (S)-BINOL and L-prolineamide promoted the reaction and gave the products in good yields with up to 82 % ee.

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.

Enantioselective organocatalytic domino synthesis of tetrahydropyridin-2-ols

The asymmetric synthesis of tetrahydropyridin-2-ols from enals and enaminones is described. The organocatalytic domino reaction involves a Michael addition-hemiaminalization sequence using the Jørgensen-Hayashi catalyst. Dehydration or oxidation leads to the corresponding 1,4-dihydro-pyridines or 3,4-dihydropyridin-2-ones in a one-pot fashion.

Formal synthesis of TMC-69-6H via a one-pot enantioselective domino proline-mediated aldol/olefin homologation procedure

Enantioselective synthesis of TMC-69-6H was accomplished from readily accessible pyridone derivative via a domino proline-mediated aldol reaction/olefin homologation, followed by tandem ring-closing and cross metathesis.

A Unified Strategy for the Asymmetric Total Syntheses of Diversonol and Lachnone C

A unified synthetic strategy for the asymmetric syntheses of the natural products diversonol and lachnone C was developed by using the domino vinylogous aldol-oxa-Michael reaction as the enantioselective key step. Further transformations include dihydroxylation, lactol-opening by a Wittig-reaction, and lactonization. The obtained chromone lactones, a class of mycotoxins, can further be converted to tetrahydroxanthones by a Dieckmann condensation. This general method allows for the first time the enantioselective access to these classes of natural products and should be applicable to other members of the tetrahydroxanthone and chromone lactone families.

Enantioselective Synthesis of 2‐Substituted‐1,5‐Benzodiazepines through Domino Reaction of o‐Phenylenediamine and Chalcone Derivatives

AbstractChiral 2‐substituted‐1,5‐benzodiazepine derivatives were synthesized for the first time from an enantioselective domino reaction involving o‐phenylenediamine and 2′‐hydroxychalcones. The titanium complex formed from chiral ligand 1a derived from (S)‐BINOL and L‐prolineamide promoted the reaction and gave the products in good yields with up to 82 % ee.

ChemInform Abstract: Catalytic Batch and Continuous Flow Production of Highly Enantioenriched Cyclohexane Derivatives with Polymer‐Supported Diarylprolinol Silyl Ethers.

AbstractThe known prolinol ether (Ia) and the new derivative (Ib) are tested in the enantioselective domino Michael—Knoevenagel reaction of aldehyde (II) with diester (III).

Catalytic Batch and Continuous Flow Production of Highly Enantioenriched Cyclohexane Derivatives with Polymer-Supported Diarylprolinol Silyl Ethers

Diarylprolinol silyl ethers immobilized onto polystyrene have been employed as catalysts in the enantioselective domino Michael―Knoevenagel reaction of dimethyl 3-oxoglutarate and 3-substituted acrolein derivatives, including aliphatic ones. The best catalyst allows the preparation of highly functionalized cyclohexane derivatives in a straightforward and efficient manner, both under batch and continuous flow conditions.

Enantioselective organocatalytic domino Michael–acetalization–Henry reactions of 2-hydroxynitrostyrene and aldehyde for the synthesis of tetrahydro-6H-benzo[c]chromenones

Asymmetric domino Michael-acetalization reactions of 2-hydroxynitrostyrene and aldehydes "on water" followed by oxidation providing the cis-3,4-disubstituted dihydrocoumarins with excellent enantioselectivities (up to >99% ee). The variant with glutaraldehyde underwent a highly stereoselective domino Michael-acetalization-Henry reaction to afford the tetrahydro-6H-benzo[c]chromen-6-ones after the subsequent oxidation.