An effective palladium-catalyzed regioselective hydroformylation of olefins with formic acid is described. The ligand plays a crucial role in directing the reaction pathway. Linear aldehydes can be obtained in up to 93% yield with >20:1 regioselectivity using 1,3-bis(diphenylphosphino)propane (dppp) as the ligand. The reaction process is operationally simple and requires no syngas.

Multicomponent reactions that involve interception of onium ylides through Aldol, Mannich, and Michael addition with corresponding bench-stable acceptors have demonstrated broad applications in synthetic chemistry. However, because of the high reactivity and transient survival of these in situ generated intermediates, the substitution-type interception process, especially the asymmetric catalytic version, remains hitherto unknown. Herein, a three-component asymmetric allylation of α-diazo carbonyl compounds with alcohols and allyl carbonates is disclosed by employing a ternary cooperative catalysis of achiral Pd-complex, Rh 2 (OAc) 4 , and chiral phosphoric acid CPA. This method represents the first example of three-component asymmetric allylic alkylation through an S N 1-type trapping process, which involves a convergent assembly of two active intermediates, Pd-allyl species, and enol derived from onium ylides, providing an expeditious access to chiral α,α-disubstituted ketones in good to high yields with high to excellent enantioselectivity. Combined experimental and computational studies have shed light on the mechanism of this novel three-component reaction, including the critical role of Xantphos ligand and the origin of enantioselectivity.

An effective Pd-catalyzed hydrocarboxylation of aryl olefins with AcO and formic acid is described. A variety of 2- and 3-arylpropanoic acids can be regioselectively formed by the judicious choice of ligand without the use of toxic CO gas.

An effective Pd-catalyzed regiodivergent hydroesterification of aryl olefins with phenyl formate is described. Either linear or branched phenyl arylpropanoates can be obtained in good yields with high regioselectivities by the judicious choice of ligand without the use of toxic CO gas.

A solid complex, conveniently prepared from commercially available sodium triphenylphosphine-m-sulfonate (TPPMS) and carbon tetrabromide, can be used as an easily recoverable and reusable catalyst system for Friedel–Crafts alkylation of indoles with carbonyl compounds or acetals to produce bis(indolyl)alkane products (BIAs).