111479-60-8Relevant academic research and scientific papers
Stereoselective synthesis of substituted N-heterocycles via sequential cross metathesis-reductive cyclization
Gebauer, Julian,Dewi, Purnama,Blechert, Siegfried
, p. 43 - 46 (2005)
A diastereoselective synthesis of substituted piperidine and pyrrolidine derivatives is presented, employing a highly selective cross metathesis (CM) reaction followed by a domino reduction-cyclization process. A diastereoselective synthesis of substituted mono- and bicyclic-piperidine and pyrrolidine derivatives is presented, employing a highly selective cross metathesis (CM) reaction followed by a domino reduction-cyclization process.
Convenient preparations of racemic and enantiopure methyl 6-oxopipecolate
Davies, Catherine E.,Heightman, Thomas D.,Hermitage, Stephen A.,Moloney, Mark G.
, p. 687 - 696 (1996)
Short, convenient syntheses of racemic and enantiopure methyl 6-oxopipecolate are described, starting from either pipecolic acid or (S)-lysine respectively. The sequence for the latter compound relies upon improved methodology for the oxidation of C-6 of
Interrupted Pyridine Hydrogenation: Asymmetric Synthesis of δ-Lactams
Wagener, Tobias,Lückemeier, Lukas,Daniliuc, Constantin G.,Glorius, Frank
supporting information, p. 6425 - 6429 (2021/02/22)
Metal-catalyzed hydrogenation is an effective method to transform readily available arenes into saturated motifs, however, current hydrogenation strategies are limited to the formation of C?H and N?H bonds. The stepwise addition of hydrogen yields reactive unsaturated intermediates that are rapidly reduced. In contrast, the interruption of complete hydrogenation by further functionalization of unsaturated intermediates offers great potential for increasing chemical complexity in a single reaction step. Overcoming the tenet of full reduction in arene hydrogenation has been seldom demonstrated. In this work we report the synthesis of sought-after, enantioenriched δ-lactams from oxazolidinone-substituted pyridines and water by an interrupted hydrogenation mechanism.
Does the Exception Prove the Rule? A Comparative Study of Supramolecular Synthons in a Series of Lactam Esters
Weck,Nauha,Gruber
, p. 2899 - 2911 (2019/05/10)
In this paper a series of simple lactam esters and carboxylic acids is studied with respect to their overall conformation and hydrogen bonding patterns. In total, eight lactams featuring Nα-substitution have been synthesized. Additionally, the molecular structures of related lactam esters have been considered. The length of the amide bonds does not seem to be majorly influenced by different substituents unless the electron withdrawing N-Boc-protection group is introduced, resulting in a higher susceptibility toward hydrolytic ring opening. As known from other lactams, the Nα ester moiety of the title compounds can be in an axial or equatorial conformation. Smaller ester groups were found to prefer equatorial positions, while larger ones occupy axial sites. N-substitution seems to promote axial conformations of the respective Nα group, with enantholactams being the only studied exception. In addition to the two common amide packing motifs, i.e., the R2 2 (8) amide dimer (NH···O/NH···O) and the C(4) amide chain, a third graph-set was found: the R2 2(8) NH···O/CH···O=C heterodimer. In general, there seems to be a tendency for medium-sized lactams as well as lactams with small esters to form R2 2 (8) amide dimers. Larger esters and enantholactam esters lead to C(4) amide chains. In this respect the formation of R2 2(8) N - H···O/C-H···O=C heterodimers should be seen as a remarkable exception.
Reactivity of a propiolate dimer with nucleophiles and an efficient synthesis of dimethyl α-aminoadipate
Zhou, Li-Hong,Yu, Xiao-Qi,Pu, Lin
experimental part, p. 425 - 427 (2010/03/04)
An enyne dimer (1) of methyl propiolate was reacted with amines to form dimethyl (E,E)-2-amino-2,4-hexadiene dioates with remarkable chemospecificity, regiospecificity, and stereospecificity. This enyne was also reduced by Ph3P stereospecifically to form dimethyl (E,E)-muconic ester. Hydrogenation of the conjugated amino-diene led to an efficient production of dimethyl α-aminoadipate. A lactam of dimethyl α-aminoadipate was obtained in high yield by simply varying the hydrogenation conditions.
Lactams as prostanoid receptor ligands. Part 4: 2-Piperidones as selective EP4 receptor agonists
Elworthy, Todd R.,Brill, Emma R.,Caires, Christopher C.,Kim, Woongki,Lach, Leang K.,Tracy, Jahari Laurant,Chiou, San-San
, p. 2523 - 2526 (2007/10/03)
2-Piperidones were prepared bearing heptanoic acid or a thioether heptanoic acid at the 1-position as well as appropriately substituted at the 6-position to mimic the structure of prostaglandins. The stereochemical purity at the 6-position was determined to be ≥95% ee for an advanced synthetic intermediate. The 2-piperidones were identified as potent agonists at the EP4 prostanoid receptor. They displayed a high affinity (K i 5-130 nM) at EP4 and subtype selectivity.
Radical Chain Reactions of α-Azido-β-keto Esters with Tributyltin Hydride. a Novel Entry to Amides and Lactams through Regiospecific Nitrogen Insertion
Benati, Luisa,Nanni, Daniele,Sangiorgi, Corrado,Spagnolo, Piero
, p. 7836 - 7841 (2007/10/03)
A variety of acyclic and carbocyclic α-azido-β-keto esters have been readily prepared from the parent dicarbonyl compounds, and their radical chain reactions with tributyltin hydride have been investigated. These reactions normally result in efficient production of alkoxycarbonyl-substituted amides and lactams and thence provide a new, useful method for regiospecific nitrogen insertion of keto ester compounds. The likely mechanism entails initial addition of tributylstannyl radical to the azido moiety to give a stannylaminyl radical, which readily undergoes intramolecular three-membered cyclization onto the ketone group to form an alkoxyl radical. The alkoxyl radical then undergoes regiospecific β-scission to form a stable ring-opened radical that is eventually reduced by tributyltin hydride to propagate the chain. With certain substrates, concomitant deazidation occurs to an important extent. This process, which is unusually observed in radical reactions of alkyl azides, is ascribed to addition of the stannyl radical to the terminal azido nitrogen; subsequent fragmentation of the ensuing 1,3-triazenyl adduct gives stannyl azide and a deazidated alkyl radical, resonance-stabilized by the adjacent carbonyl groups. The radical reactions of 2-azido-2-(ethoxycarbonyl)-1-tetralone with allyltributylstannane and allyltriphenylstannane have also been investigated with the (missed) aim to achieve nitrogen insertion and concomitant allylation.
ALKYLATION OF SHIFF BASE ANIONS WITH ω-HALOGENO ESTERS: A LACTAM SYNTHESIS.
Mkhairi, A,Hamelin, J.
, p. 4435 - 4436 (2007/10/02)
Imine anions of α-aminoesters, obtained from NaH/DMSO are alkylated with ω-halogenoesters.Thermolysis of the alkylated compounds lead to functionnalized lactams.
