188869-25-2Relevant articles and documents
Convenient synthesis of substituted piperidinones from α,β- unsaturated amides: Formal synthesis of deplancheine, tacamonine, and paroxetine
Takasu, Kiyosei,Nishida, Naoko,Tomimura, Akiko,Ihara, Masataka
, p. 3957 - 3962 (2005)
An intermolecular aza-double Michael reaction leading to functionalized piperidin-2-ones from simple starting materials has been developed. The method allows α,β-unsaturated amides to be used as a synthon of the piperidine nucleus. In addition, the utilit
Transition-Metal-Free Multiple Functionalization of Piperidines to 4-Substituted and 3,4-Disubstituted 2-Piperidinones
Chamorro-Arenas, Delfino,Nolasco-Hernández, Alejandro A.,Fuentes, Lilia,Quintero, Leticia,Sartillo-Piscil, Fernando
, p. 4671 - 4676 (2020/03/10)
Remote and multiple functionalization of piperidines without the use of transition-metal catalysts and elaborate directing groups is one of the major challenges in organic synthesis. Herein is reported an unprecedented two-step protocol that enables the multiple functionalization of piperidines to either 4-substituted or trans-3,4-disubstituted 2-piperidones. First, by exploiting the duality of TEMPO reactivity, which under oxidative and thermal conditions fluctuates between cationic and persistent-radical form, a novel multiple C(sp3)-H oxidation of piperidines to α,β-unsaturated 2-piperidones was developed. Second, the intrinsic low reactivity of the unsaturated piperidones toward conjugated Grignard additions was overcome by using trimethylsilyl chloride (TMSCl) as Lewis acid. Subsequently, conjugated Grignard addition/electrophilic trapping protocol provided substituted 2-piperidone intermediates, some of which were then transformed into pharmaceutical alkaloids.
Palladium-Catalyzed Asymmetric Allylic Allylation of Racemic Morita–Baylis–Hillman Adducts
Wang, Xubin,Wang, Xiaoming,Han, Zhaobin,Wang, Zheng,Ding, Kuiling
, p. 1116 - 1119 (2017/01/18)
A palladium-catalyzed asymmetric allyl–allyl cross-coupling of acetates of racemic Morita–Baylis–Hillman adducts and allylB(pin) has been developed using a spiroketal-based bis(phosphine) as the chiral ligand, thus affording a series of chiral 1,5-dienes bearing a vinylic ester functionality in good yields, high branched regioselectivities, and uniformly excellent enantioselectivities (95–99 % ee). Further synthetic manipulations of the allylation products provided novel ways for rapid access to a range of chiral polycyclic lactones and polycyclic lactams, as well as the antidepressant drug (?)-Paroxetine, in high optical purities.
Optically pure γ-butyrolactones and epoxy esters via two stereocentered HKR of 3-substituted epoxy esters: A formal synthesis of (-)-paroxetine, Ro 67-8867 and (+)-eldanolide
Devalankar, Dattatray A.,Karabal, Pratibha U.,Sudalai, Arumugam
supporting information, p. 1280 - 1285 (2013/05/08)
The HKR of racemic anti- or syn-3-substituted epoxy esters catalyzed by a Co(iii)salen complex provides ready access to the corresponding enantioenriched 3,4-disubstituted γ-butyrolactones and 3-substituted epoxy esters. This strategy has been successfully employed in the formal synthesis of biologically active 3,4-disubstituted piperidine derivatives, (-)-paroxetine and Ro 67-8867 and a natural product, (+)-eldanolide.
