511-26-2Relevant articles and documents
Radical dehydroxylative alkylation of tertiary alcohols by Ti catalysis
Xie, Hao,Guo, Jiandong,Wang, Yu-Quan,Wang, Ke,Guo, Peng,Su, Pei-Feng,Wang, Xiaotai,Shu, Xing-Zhong
supporting information, p. 16787 - 16794 (2020/11/09)
Deoxygenative radical C?C bond-forming reactions of alcohols are a long-standing challenge in synthetic chemistry, and the current methods rely on multistep procedures. Herein, we report a direct dehydroxylative radical alkylation reaction of tertiary alcohols. This new protocol shows the feasibility of generating tertiary carbon radicals from alcohols and offers an approach for the facile and precise construction of all-carbon quaternary centers. The reaction proceeds with a broad substrate scope of alcohols and activated alkenes. It can tolerate a wide range of electrophilic coupling partners, including allylic carboxylates, aryl and vinyl electrophiles, and primary alkyl chlorides/bromides, making the method complementary to the cross-coupling procedures. The method is highly selective for the alkylation of tertiary alcohols, leaving secondary/primary alcohols (benzyl alcohols included) and phenols intact. The synthetic utility of the method is highlighted by its 10-g-scale reaction and the late-stage modification of complex molecules. A combination of experiments and density functional theory calculations establishes a plausible mechanism implicating a tertiary carbon radical generated via Ti-catalyzed homolysis of the C?OH bond.
A nitrogen-ligated nickel-catalyst enables selective intermolecular cyclisation of β- And γ-amino alcohols with ketones: Access to five and six-membered N-heterocycles
Singh, Khushboo,Vellakkaran, Mari,Banerjee, Debasis
supporting information, p. 2250 - 2256 (2018/05/30)
Owing to the great demand for the synthesis of N-heterocycles, development of new reactions that utilise renewable resources and convert them into key chemicals using non-precious base metal-catalysts is highly desirable. Herein, we demonstrated a sustainable Ni-catalysed dehydrogenative approach for the synthesis of pyrroles, pyridines, and quinolines by the reaction of β- and γ-amino alcohols with ketones via C-N and C-C bond formations in a tandem fashion. A variety of aryl, hetero-aryl, and alkyl ketones having free amine, halide, alkyl, alkoxy, alkene, activated benzyl, and pyridine moieties were converted into synthetically interesting 2,3 and 2,3,5-substituted bicyclic as well as tricyclic N-heterocycles with up to 90% yields. As a highlight, we demonstrated the synthesis of an interesting pyrrole derivative by intermolecular cyclisation of a steroid hormone with phenylalaninol.
Stereochemical assignment of c-24 and c-25 of amarasterone a, a putative biosynthetic intermediate of cyasterone
Hirayama, Yui,Okuzumi, Keiko,Masubuti, Hironori,Uekusa, Hidehiro,Girault, Jean-Pierre,Fujimoto, Yoshinori
, p. 5471 - 5477 (2014/07/08)
A C29 phytoecdysteroid named amarasterone A (1) has been isolated from Cyathula capitata (Amaranthaceae), Leuzea carthamoides (Asteraceae), and Microsorum scolopendria (Polypodiaceae). We recently isolated amarasterone A from C. officinalis. Am
