748-97-0Relevant articles and documents
Rh-Catalyzed Coupling of Aldehydes with Allylboronates Enables Facile Access to Ketones
Zhang, Kezhuo,Huang, Jiaxin,Zhao, Wanxiang
supporting information, (2022/02/21)
We present herein a novel strategy for the preparation of ketones from aldehydes and allylic boronic esters. This reaction involves the allylation of aldehydes with allylic boronic esters and the Rh-catalyzed chain-walking of homoallylic alcohols. The key to this successful development is the protodeboronation of alkenyl borylether intermediate via a tetravalent borate anion species in the presence of KHF2 and MeOH. This approach features mild reaction conditions, broad substrate scope, and excellent functional group tolerance. Mechanistic studies also supported that the tandem allylation and chain-walking process were involved.
Preparation of α,n-dilithiotoluene equivalents. Synthesis of tamoxifen
Yus, Miguel,Ramón, Diego J.,Gómez, Inmaculada
, p. 3219 - 3225 (2007/10/03)
The successive reaction of chlorobenzyl alcohols with n-butyllithium and lithium powder in the presence of a substoichiometric amount of 4,4′-di-tert-butylbiphenyl (DTBB) at -78°C yields the expected (lithiooxymethyl)phenyllithium derivative, which is trapped by reaction with different ketones. The subsequent arene-catalysed lithiation at 25°C permits the one-pot chemoselective lithiation of the primary benzyl alcoholate in the presence of a tertiary one. These new functionalised benzyllithium derivatives react with different electrophilic compounds, such as aldehydes, ketones and chlorotrimethylsilane, to give after hydrolysis the expected functionalised benzyl alcohols. Some of these alcohols are successfully transformed into mono- or di-olefins by acidic treatment. This whole strategy is applied to the preparation of anti-cancer drug tamoxifen.
Synthesis of Tamoxifen and 4-Hydroxytamoxifen using Super-base-metalated Propylbenzene
Olier-Reuchet, Chantal,Aitken, David J.,Bucourt, Robert,Husson, Henri-Philippe
, p. 8221 - 8224 (2007/10/02)
Propylbenzene is metalated regioselectively at the α-carbon using the n-BuLi-t-BuOK-TMEDA super-base combination; the resulting carbanion condenses with functionalised benzophenones to provide direct syntheses of tamoxifen and 4-hydroxytamoxifen.
