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Rare-earth silylamides serve as good catalysts for monoinsertion of isocyanides into terminal alkynes in the presence of amine additives, leading to 1-aza-1,3-enyens in excellent yields. Mechanistic investigation reveals that the amine additives play an important role as proton sources to prevent the oligomerization of isocyanides and as suitable ligands to activate the rare earth catalysts.

Regio- and stereoselective dimerization of terminal alkynes to produce conjugated enynes are achieved using rare-earth silylamide catalysts and amine additives. Dimerization of aromatic terminal alkynes, followed by hydrophosphination with diphenylphosphine enables highly efficient synthesis of 1-phosphinyl-1,3-butadienes in one-pot using single rare-earth catalysts.

Research has been conducted on the acylphosphonates and carbonyl compounds couplings that lead to beta-hydroxyphosphonates. The use of low-valent samariums is discussed.

Researchers have discovered the usefulness of ytterbium as a catalyst for achieving good yields of aminosilanes. This was achieved through the dehydrogenative silylation of primary and secondary amines with triphenysilane using ytterbium as a major catalyst. In the past, such chemical transformations were catalyzed using trivalent lanthanocene complexes, which were later found to be difficult for shipping, handling and large-scale synthesis.

A study was conducted to analyze the catalytic dehydrogenative silylation of terminal alkynes supporting hydrosilanes using divalent ytterbium-imine complexes. During the reaction of dihydrosilanes, the product distribution was obtained based on the ratio of 1-hexyne to the silanes. The reactivities of different monohydrosilanes were also evaluated. Results indicated the effectiveness of using ytterbium-imine catalysts in the dehydrogenative silylation of terminal alkynes supporting hydrosilane.

Bond fission of the C-O bond of allylic benzyl ethers with Cp*2Sm(thf)n produced samarium complexes in good yields. Ease of cleavage was observed to be comparable to the corresponding propargylic ethers intermolecularly, but lower intramolecularly. Regio- and stereochemistry on the electrophilic trappings of the allylic complexes produced were dependent on the type of electrophiles. They reacted with carbonyl compounds exclusively from the most substituted terminus of the allylic moieties to produce blanched homoallylic alcohols with anti-diastereoselectivity.

An exclusive sp2 C-O bond cleavage of alkyl vinyl ethers with divalent samariums to generate vinylsamarium complexes together with the corresponding alkoxides is presented. Samarium enolates and benzyl species are also selectively generated from benzyl vinyl ethers by sp3 C-O fission. These were the results of an examination of regioselectivity on the reductive cleavage of alkyl vinyl ethers, or the competition between sp2 C-O fission leading to vinyl species and alkoxides and sp3 C-O enolates and alkyl complexes. Selectivity was found to be dependent on the alkyl substituents.

Research has been conducted on alkynes. The authors describe the intermolecular hydrophosphination of these compounds with diphenylphosphine catalyzed by ytterbium-imine complex to produce phosphine oxides and alkenylphosphines.