Straightforward synthesis of 2-propylquinolines under multicomponent conditions in fluorinated alcohols

HFIP in Organic Synthesis

1,1,1,3,3,3-Hexafluoroisopropanol (HFIP) is a polar, strongly hydrogen bond-donating solvent that has found numerous uses in organic synthesis due to its ability to stabilize ionic species, transfer protons, and engage in a range of other intermolecular interactions. The use of this solvent has exponentially increased in the past decade and has become a solvent of choice in some areas, such as C-H functionalization chemistry. In this review, following a brief history of HFIP in organic synthesis and an overview of its physical properties, literature examples of organic reactions using HFIP as a solvent or an additive are presented, emphasizing the effect of solvent of each reaction.

Friedel–Crafts alkylation reaction with fluorinated alcohols as hydrogen-bond donors and solvents

An effective and clean FC alkylation of indoles and electron-rich arenes with β-nitroalkenes in HFIP was reported. The desired products are formed rapidly in excellent yields under mild conditions without the need for any additional catalysts or reagents. Further, this methodology can be applied to one-pot synthesis of biologically active tryptamine derivatives.

Friedel–Craft alkylation of heterocycle derivatives with β-nitroalkenes was performed in HFIP. The one-pot synthesis of tryptamines could be applied.

Efficient synthesis of 2,4-disubstituted quinolines: calix[n]arene-catalyzed Povarov-hydrogen-transfer reaction cascade

A new calixarene-catalyzed cascade process, involving Povarov reaction and hydrogen transfer, for the synthesis of 2,4-disubstituted quinolines is described.