55002-83-0Relevant articles and documents
Palladium-Catalyzed Regioselective Alkynylation of Pyrroles and Azoles under Mild Conditions: Application to the Synthesis of a Dopamine D-4 Receptor Agonist
Brachet, Etienne,Belmont, Philippe
, p. 7519 - 7529 (2015)
A mild and general method for the direct alkynylation of azoles such as pyrrole, indole, and 7-azaindole is described here. Using a simple catalytic system such as Pd(OAc)2 (2.5 mol %), P(tBu)2Me·HBF4 (5 mol %), and NaOAc (2 equiv) allowed the regioselective introduction of various alkynyl residues at the C-2 position of pyrroles. Interestingly, C-2 alkynylation was also observed on C-3-substituted indoles, whereas classical C-3 alkynylation was obtained on selected unsubstituted indoles and 7-azaindole. Our methodology has been illustrated by the efficient synthesis of a potential schizophrenia drug (dopamine D-4 inhibitor).
Directed Nickel-Catalyzed pseudo-Anomeric C?H Alkynylation of Glycals as an Approach towards C-Glycoconjugate Synthesis
de Robichon, Morgane,Branquet, David,Uziel, Jacques,Lubin-Germain, Nadège,Ferry, Angélique
, p. 5138 - 5148 (2021/09/22)
The synthesis of complex C-glycoconjugates is presented here using a key directed nickel-catalyzed C?H alkynylation step. Thanks to a bidentate amidoquinoline-type directing group, the insertion of diverse alkynyl moieties onto the pseudo-anomeric position of glycal substrates was performed on ten examples in moderate to good yields. These platforms were used as starting substrates in a click reaction with complex azides to form original C-glycoconjugates. By this route, a C-glycosylated amino acid, a C-linked disaccharide and a C-glycosylated biotin derivative were synthesized. Preliminary conditions to remove the directing group are also proposed. (Figure presented.).
Diisobutylaluminum Hydride Promoted Cyclization of 1-Hydrosilyl-4-silyl-1,3-enynes to Polysubstituted Siloles
Kinoshita, Hidenori,Ueda, Akihiro,Fukumoto, Hiroki,Miura, Katsukiyo
supporting information, p. 882 - 885 (2017/02/26)
An efficient method for preparing unsymmetrically multisubstituted siloles is described. The reaction of 1-hydrosilyl-4-silyl-1,3-enynes with diisobutylaluminum hydride (DIBAL-H) gave multisubstituted siloles in good to high yields. This method could be applied to the synthesis of benzosiloles using 2-hydrosilyl-1-(silylethynyl)benzenes as substrates. The silole formation was also promoted even by a substoichiometric amount of DIBAL-H. The reaction provides a straightforward method to prepare siloles and benzosiloles.
