105706-83-0Relevant academic research and scientific papers
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
supporting information, 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.
Preparation of aα,β-Unsaturated Lactams through intramolecular electrophilic carbamoylation of Alkenes
Yasui, Yoshizumi,Kakinokihara, Issei,Takeda, Hiroshi,Takemoto, Yoshiji
experimental part, p. 3989 - 3993 (2010/03/24)
A general, synthetic method for the preparation of α, βunsaturated lactams startingsei from alkenylchloroformamides has been developed. The reaction was complete within five minutes at 150 °C in N-methylpyrrolidone with a catalytic amount of HBr under mic
New synthesis of heterocycles by use of palladium catalyzed cycli zation of α-haloamide with internal double bond
Mori, Miwako,Kanda, Nana,Oda, Izumi,Ban, Yoshio
, p. 5465 - 5474 (2007/10/02)
α-Haloamide having internal double bond was allowed to react with a catalytic amount of Pd(PPh3)4 in the presence of base to produce a cyclized product in a fairly good yield possibly through the intermediate of -alkylmetal complex. By use of this method, five and six membered lactams, pyrrolizidine and quinolizidine derivatives were synthesized in fairly good yields.
