1047660-72-9Relevant articles and documents
Ru-Catalyzed Geminal Hydroboration of Silyl Alkynes via a New gem-Addition Mechanism
Feng, Qiang,Wu, Haonan,Li, Xin,Song, Lijuan,Chung, Lung Wa,Wu, Yun-Dong,Sun, Jianwei
supporting information, p. 13867 - 13877 (2020/09/21)
While 1,2-addition represents the most common mode of alkyne hydroboration, herein we describe a new 1,1-hydroboration mode. It is the first demonstration of gem-(H,B) addition to an alkyne triple bond. With the superior [CpRu(MeCN)3]PF6 catalyst, a range of silyl alkynes reacted efficiently with HBpin under mild conditions to form various synthetically useful silyl vinyl boronates with complete stereoselectivity and broad functional group compatibility. An extension to germanyl alkynes and the hydrosilylation of alkynyl boronates toward the same type of products were also achieved. Mechanistically, this process features a new pathway featuring gem-(H,B) addition to form the key α-boryl-α-silyl Ru-carbene intermediate followed by silyl migration. It is believed that the orbital interaction between boron and Cβ in the coplanar relationship between the boron atom and the ruthenacyclopropene ring preceding boron migration is responsible for the new reactivity. Control experiments and DFT (including molecular dynamics) calculations provided important insights into the mechanism, which excluded the involvement of a metal vinylidene intermediate. This study represents a new step forward not only for alkyne hydroboration but also for other geminal additions of alkynes.
An orthogonally protected CycloTriVeratrylene (CTV) as a highly pre-organized molecular scaffold for subsequent ligation of different cyclic peptides towards protein mimics
Longin, Ond?ej,van de Langemheen, Helmus,Liskamp, Rob M.J.
, p. 5008 - 5015 (2017/09/19)
The synthesis of a semi-orthogonally protected CycloTriVeratrilene (CTV) scaffold derivative as well as the sequential introduction of three different peptide loops onto this molecular scaffold via Cu(I)-catalyzed azide alkyne cycloaddition towards a medium-sized protein mimic is described. This approach for the construction of medium-sized protein mimics is illustrated by the synthesis of a paratope mimic of the monoclonal antibody Infliximab (Remicade) and provides access to a range of highly pre-organized molecular constructs bearing three different peptide segments. This approach may find wide applications for development of protein-protein interaction disruptors as well as synthetic vaccines.
