Reductive CO 2 Homocoupling: Synthesis of a Borylated C 3 Carbohydrate

Aurélien Béthegnies (1) , Yannick Escudié (1) , Nelson Nuñez‐dallos (1, 2) , Laure Vendier (1) , John Hurtado (2) , Iker Del rosal (3) , Laurent Maron (3) , Sébastien Bontemps (1)

1 LCC - Laboratoire de chimie de coordination
2 UNIANDES - Universidad de los Andes [Bogota]
3 LPCNO - Laboratoire de physique et chimie des nano-objets

To use carbon dioxide as a source of carbon, recent progress has been made toward the synthesis of higher value chemicals and in particular toward Cn compounds. In this context, we report here the synthesis of a borylated C3-carbohydrate from CO2 as the only source of carbon. This result corresponds to the unprecedented formation of a polyol chain and of asymmetric carbon atoms from CO2. The adopted strategy involves the Fe-catalysed selective 4e− reduction of CO2 into bis(boryl)acetal followed in one-pot by a carbene-mediated C−C coupling reaction. Boron is shown to play a key role in the coupling step enabling to observe the first diastereoselective formose-type reaction. This result is in addition obtained under mild reaction conditions (T<80 °C, 1 atm of CO2) and short reaction time (t<2 h).

Mots clés: CO2; borane; carbohydrate; carbine; formose

Domaines: Chimie de coordination

Aurélien Béthegnies, Yannick Escudié, Nelson Nuñez‐dallos, Laure Vendier, John Hurtado, et al.. Reductive CO 2 Homocoupling: Synthesis of a Borylated C 3 Carbohydrate. ChemCatChem, 2019, 11, pp.760-765. ⟨10.1002/cctc.201801875⟩. ⟨hal-02330570⟩