Using carbon dioxide as a building block in organic synthesis

Ring-opening copolymerisation of cyclohexene oxide and carbon dioxide catalysed by scorpionate zinc complexes

New bimetallic heteroscorpionate zinc complexes have been developed and used as efficient catalysts for the synthesis of poly(cyclohexene carbonate).

La–Mg mixed oxide as a highly basic water resistant catalyst for utilization of CO2 in the synthesis of quinazoline-2,4(1H,3H)-dione

Synthesis of quinazoline-2,4(1H,3H)-dione using La–Mg mixed oxide in water.

Structural diversity in metal–organic nanoparticles based on iron isopropoxide treated lignin

The magnetic nature of iron-containing nanoparticles enables multiple high-end applications.

Double carboxylation of o-alkynyl acetophenone with carbon dioxide

A copper-catalyzed double carboxylation of o-alkynyl acetophenone using carbon dioxide via a carboxylation/intramolecular cyclization/second carboxylation sequence to afford 1(3H)-isobenzofuranylidene dicarboxylic esters in good yields is developed.

Organocatalysts with carbon-centered activity for CO2 reduction with boranes

We report two organocatalysts for CO2 hydroboration to methylborylethers, which upon hydrolysis can produce methanol. These organocatalysts feature carbon-centered reversible CO2 binding, broad borane scopes, and high catalytic activities.

Hydrophosphination of CO2 and subsequent formate transfer in the 1,3,2-diazaphospholene-catalyzed N-formylation of amines

Hydrophosphination of CO2 with 1,3,2-Diazaphospholene (NHP-H; 1) afforded phosphorus formate (NHP-OCOH; 2) through the formation of a bond between the electrophilic phosphorus atom in 1 and the oxygen atom from CO2 , along with hydride transfer to the carbon atom of CO2 . Transfer of the formate from 2 to Ph2 SiH2 produced Ph2 Si(OCHO)2 (3) in a reaction that could be carried out in a catalytic manner by using 5 mol % of 1. These elementary reactions were applied to the metal-free catalytic N-formylation of amine derivatives with CO2 in one pot under ambient conditions.

C-N and N-H Bond Metathesis Reactions Mediated by Carbon Dioxide

Herein, we report CO2 -mediated metathesis reactions between amines and DMF to synthesize formamides. More than 20 amines, including primary, secondary, aromatic, and heterocyclic amines, diamines, and amino acids, are converted to the corresponding formamides with good-to-excellent conversions and selectivities under mild conditions. This strategy employs CO2 as a mediator to activate the amine under metal-free conditions. The experimental data and in situ NMR and attenuated total reflectance IR spectroscopy measurements support the formation of the N-carbamic acid as an intermediate through the weak acid-base interaction between CO2 and the amine. The metathesis reaction is driven by the formation of a stable carbamate, and a reaction mechanism is proposed.

Enantioselective small molecule synthesis by carbon dioxide fixation using a dual Brønsted acid/base organocatalyst

Carbon dioxide exhibits many of the qualities of an ideal reagent: it is nontoxic, plentiful, and inexpensive. Unlike other gaseous reagents, however, it has found limited use in enantioselective synthesis. Moreover, unprecedented is a tool that merges one of the simplest biological approaches to catalysis-Brønsted acid/base activation-with this abundant reagent. We describe a metal-free small molecule catalyst that achieves the three component reaction between a homoallylic alcohol, carbon dioxide, and an electrophilic source of iodine. Cyclic carbonates are formed enantioselectively.

A recyclable CO surrogate in regioselective alkoxycarbonylation of alkenes: indirect use of carbon dioxide

Herein, we report a Pd-catalysed alkoxycarbonylation of alkenes based on the use of a recyclable CO₂reduction product, the crystalline and air-stableN-formylsaccharin, as a CO surrogate.

A facile one-step synthesis of star-shaped alkynyl carbonates from CO2

The synthesis of new star-shaped compounds containing three or six pendant carbonates with terminal alkynes at 1 atm CO₂ and room temperature.

Reactivity of carbon dioxide in hydrofluoroethers: a facile access to cyclic carbonates

The reactivity of CO₂ dissolved in high quantities in hydrofluoroethers was enhanced and allowed the formation of cyclic carbonates from epoxides with excellent selectivities.

Phosphonium salt incorporated hypercrosslinked porous polymers for CO2 capture and conversion

Hypercrosslinked porous phosphonium polymers for selective CO₂ capture and conversion.

Carboxylic acid derivatives via catalytic carboxylation of unsaturated hydrocarbons: whether the nature of a reductant may determine the mechanism of CO2incorporation?

Advances and recent breakthroughs in catalytic synthesis of carboxylic acids and their derivatives starting from unsaturated hydrocarbons are discussed.