1025-56-5Relevant articles and documents
Synthesis of Functionalized Pyrrolidines from N-(Benzylidene)- and N-(Alkylidene)-homoallylamines
Smaele Dirk De,Kimpe, Norbert De
, p. 2029 - 2030 (1995)
N-(Benzylidene)- and N-(alkylidene)-homoallylamines are cyclised by electrophiles, e.g. bromine or phenylselenenyl bromide, and by subsequent reduction to the corresponding 3-functionalised pyrrolidines; the stereochemistry was investigated, and reductive
Selective and catalytic arylation of N-phenylpyrrolidine: sp3 C-H bond functionalization in the absence of a directing group
Sezen, Bengue,Sames, Dalibor
, p. 5284 - 5285 (2005)
We herein describe our studies on arylation of N-phenylpyrrolidine, which led to the development of a new transformation for the direct and selective arylation of sp3 C-H bonds in the absence of a directing group. In this method, Ru(H)2(CO)(PCy3)3 4 was used as the catalyst, and preliminary mechanistic studies suggested that Ru(Ph)(I)(CO)(PCy3)2 5 is the key intermediate of the catalytic cycle. A large kinetic isotope effect (kH/kD = 5.4) was observed, which supports the proposal that C-H bond metalation is the slow step. Preliminary examination of the substrate scope showed that in addition to N-phenylpyrrolidine, N-methyl- and N-benzylpyrrolidine, as well as N-benzoylpyrrolidine, were arylated under the reaction conditions. Copyright
Transition-Metal-Free Reductive Functionalization of Tertiary Carboxamides and Lactams for α-Branched Amine Synthesis
Chiba, Shunsuke,Dixon, Darren J.,Fan, Dongyang,Ong, Derek Yiren
supporting information, p. 11903 - 11907 (2020/05/22)
A new method for the synthesis of α-branched amines by reductive functionalization of tertiary carboxamides and lactams is described. The process relies on the efficient and controlled reduction of tertiary amides by a sodium hydride/sodium iodide composite, in situ treatment of the resulting anionic hemiaminal with trimethylsilyl chloride and subsequent coupling with nucleophilic reagents including Grignard reagents and tetrabutylammonium cyanide. The new method exhibits broad functional-group compatibility, operates under transition-metal-free reaction conditions, and is suitable for various synthetic applications on both sub-millimole and on multigram scales.
Reductive Alkylation of Tertiary Lactams via Addition of Organocopper (RCu) Reagents to Thioiminium Ions
Mateo, Pierre,Cinqualbre, Joséphine E.,Meyer Mojzes, Melinda,Schenk, Kurt,Renaud, Philippe
, p. 12318 - 12327 (2017/12/08)
A simple procedure for the conversion of tertiary lactams to 2-monoalkylated cyclic amines is described. The reaction sequence involves conversion of a lactam to a thioiminium ion followed by reaction with an organocopper (RCu) reagent and final reduction with triacetoxyborohydride. The reaction is high yielding and shows an excellent functional group tolerance. Its utility is demonstrated by a rapid synthesis of indolizidine 167B. The excellent chemoselectivity of the process, where only monoalkylation products are formed, is rationalized by a mechanism involving the formation of a transient enamine.
A direct and general method for the reductive alkylation of tertiary lactams/amides: Application to the step economical synthesis of alkaloid (-)-morusimic acid D
Xiao, Kai-Jiong,Wang, Yu,Huang, Ying-Hong,Wang, Xiao-Gang,Huang, Pei-Qiang
, p. 8305 - 8311 (2013/09/24)
Full details of the direct and general method for the reductive alkylation of tertiary lactams and amides to give tertiary sec-alkylamines are presented. This one-pot method consists of in situ activation of a lactam or an amide with Tf2O/DTBMP, addition of a Grignard reagent, and reduction of the resulting iminium intermediates. Alkyl, benzyl, and aryl Grignard reagents and several reductants or reducing conditions (LiAlH4, NaBH4, Hantzsch ester, Bu3SnH, Pd(OH)2/C, H2) could be used effectively. Reductive alkylations of substituted lactams demonstrated good to excellent 1,3-asymmetric induction to provide the corresponding di- or trisubstituted pyrrolidine/piperidine in 6:1 (LiAlH4), 11:1 (Et 3SiH), and 20:1 (catalytic hydrogenation) cis/trans diastereoselectivity, respectively. The versatility of this methodology was demonstrated by its application in the concise stereoselective synthesis of piperidine alkaloid (-)-morusimic acid.
The decarboxylative strecker reaction
Das, Deepankar,Richers, Matthew T.,Ma, Longle,Seidel, Daniel
, p. 6584 - 6587 (2012/01/19)
α-Amino acids react with aldehydes in the presence of a cyanide source to form α-amino nitriles in what can be considered a decarboxylative variant of the classical Strecker reaction. This unprecedented transformation does not require the use of a metal catalyst and provides facile access to valuable α-amino nitriles that are inaccessible by traditional Strecker chemistry.
Versatile one-pot reductive alkylation of lactams/amides via amide activation: Application to the concise syntheses of bioactive alkaloids (±)-bgugaine, (±)-coniine, (+)-preussin, and (-)-cassine
Xiao, Kai-Jiong,Wang, Yu,Ye, Ke-Yin,Huang, Pei-Qiang
supporting information; experimental part, p. 12792 - 12796 (2011/02/22)
Direct entry: One-pot reductive alkylation of lactams/amides with Grignard reagents has been realized via lactam/amide activation with Tf2O. This method opens a direct entry to α-alkylated amines. The versatility of the method is illustrated by the concise syntheses of bioactive alkaloids (±)-bgugaine, (±)-coniine, (+)-preussin, and (?)-cassine.
An efficient synthesis of nitrogen heterocycles by Cp*Ir-catalyzed N-cycloalkylation of primary amines with diols
Fujita, Ken-ichi,Fujii, Takeshi,Komatsubara, Atsuo,Enoki, Youichiro,Yamaguchi, Ryohei
, p. 673 - 682 (2008/09/18)
A new efficient method for the N-cycloalkylation of primary amines with diols catalyzed by a Cp*Ir complex have been developed. A variety of five-, six-, and seven-membered cyclic amines are synthesized in good to excellent yields in environmentally benign and atom economical manner with the formation of only water as a coproduct. A large scale synthesis of N-benzylpiperidine and a two-step asymmetric synthesis of (S)-2-phenylpiperidine using (R)-1-phenylethylamine as a starting primary amine have been also achieved.
The 5-endo-trig cyclization of D-glucose derived γ-alkenylamines with mercury (II) salts: Synthesis of 1-deoxy-castanospermine and its 8a-epi-analogue
Dhavale, Dilip D.,Jachak, Santosh M.
, p. 893 - 900 (2007/10/03)
The intramolecular aminomercuration of γ-alkenylamines 1a, 1b and 4 was shown to afford the 5-endo-trig cyclized product exclusively in good yield. The utility of pyrrolidine derivatives thus obtained from D-glucose derived γ-alkenylamines 1a and 1b was d
