497-89-2Relevant academic research and scientific papers
Decarboxylative Conjunctive Cross-coupling of Vinyl Boronic Esters using Metallaphotoredox Catalysis
Aggarwal, Varinder K.,Duong, Vincent K.,Mega, Riccardo S.,Noble, Adam
supporting information, p. 4375 - 4379 (2020/02/11)
The synthesis of complex alkyl boronic esters through conjunctive cross-coupling of vinyl boronic esters with carboxylic acids and aryl iodides is described. The reaction proceeds under mild metallaphotoredox conditions and involves an unprecedented decarboxylative radical addition/cross-coupling cascade of vinyl boronic esters. Excellent functional-group tolerance is displayed, and application of a range of carboxylic acids, including secondary α-amino acids, and aryl iodides provides efficient access to highly functionalized alkyl boronic esters. The decarboxylative conjunctive cross-coupling was also applied to the synthesis of sedum alkaloids.
A rapid access to (±)-sedamine and some original N -benzyl unsaturated analogues
Boussonniere, Anne,Ranaivondrambola, Tsiresy,Lebreton, Jacques,Mathe-Allainmat, Monique
experimental part, p. 2456 - 2462 (2010/09/04)
Reduction of N-alkyl-2-(2-hydroxy-2-phenylethyl)pyridinium salts using excess of sodium triacetoxyborohydride afforded exclusively the corresponding tetrahydropyridine derivative bearing a piperidine ring with a double bond in the 3,4-position. Furthermore, under these conditions, syn-1,3-amino alcohols were obtained in good yield and diastereoselectivity. Georg Thieme Verlag Stuttgart · New York.
Hydroformylation of homoallylic azides: A rapid approach toward alkaloids
Spangenberg, Thomas,Breit, Bernhard,Mann, Andre
supporting information; experimental part, p. 261 - 264 (2009/08/08)
(Chemical Equation Presented) Unprecedented hydroformylation of homoallylic azides combined with useful one-pot operations provides an expeditive access to alkaloids.
An efficient approach to 2-substituted N-tosylpiperdines: asymmetric synthesis of 2-(2-hydroxy substituted)piperidine alkaloids
Bisai, Alakesh,Singh, Vinod K.
, p. 1907 - 1910 (2007/10/03)
We have developed an efficient and a general approach to chiral 2-substituted N-tosylpiperidines starting from chiral α-substituted-N-tosylaziridines. Using this approach, we have synthesized (+)-coniine. The synthesis of chiral N-tosyl-2-piperidinylethanol 15 and ent-15, was achieved from l- and d-aspartic acids, respectively in few steps. Piperidine 15 was converted into 2-(2-hydroxysubstituted)piperidines of type 2 in optically active form. By applying this strategy, asymmetric syntheses of halosaline (R,R)-2a, (+)- and (-)-sedamine 2b, (+)- and (-)-allosedamine 2c, (+)- and (-)-sedridine 2d, (+)- and (-)-allosedridine 2e, (+)-tetraponerine T-3 3a, T-4 3c, T-7 3b, and T-8 3d have been achieved in high yields. These stereoisomers can be interconverted via Mitsunobu inversion in excellent yields.
Enantioselective synthesis of lobeline via nonenzymatic desymmetrization
Birman, Vladimir B.,Jiang, Hui,Li, Ximin
, p. 3237 - 3240 (2008/02/11)
Lobeline has been prepared in enantiopure form via desymmetrization of lobelanidine with use of BTM, a nonenzymatic enantioselective acyl transfer catalyst.
Enantioselective synthesis of (+)-sedamine and (-)-allosedamine
Yadav,Reddy, M. Sridhar,Rao, P. Purushothama,Prasad
, p. 4005 - 4012 (2008/03/11)
Two different approaches to the enantioselective syntheses of (+)-sedamine and (-)-allosedamine are described, both using the Sharpless asymmetric epoxidation as the key step. Regioselective reduction of epoxides, chemoselective oxidation of alcohols, ring-closing metathesis, and nucleophilic displacements were the other key steps employed. Georg Thieme Verlag Stuttgart.
Stereoselective synthesis of (-)-allosedamine and (1R,3R)-HPA-12 from β-p-toluenesulfonamido-γ,δ-unsaturated sulfoxide
Raghavan, Sadagopan,Rajender
, p. 5059 - 5067 (2007/10/03)
A stereoselective synthesis of (-)-allosedamine and HPA-12 is disclosed. The key steps of the synthesis include the diastereoselective synthesis of a β-sulfonamido unsaturated sulfoxide, elaboration of a bromohydrin via intramolecular sulfinyl group participation and a ring-closing metathesis reaction for the construction of the piperidine ring of allosedamine.
Stereoselective synthesis of (-)-allosedamine
Raghavan, Sadagopan,Rajender
, p. 1919 - 1922 (2007/10/03)
A stereoselective synthesis of (-)-allosedamine is disclosed. β-Aminosulfoxide 4 was generated stereoselectively by condensation of the sulfinyl anion 2 with N-Ts imine 3. The bromohydrin 5 was obtained by intramolecular sulfinyl group participation and the piperidine ring of allosedamine was elaborated using the ring-closing metathesis (RCM) reaction.
Remote Stereocenter Discrimination in the Enzymatic Resolution of Piperidine-2-ethanol. Short Enantioselective Synthesis of Sedamine and Allosedamine
Angoli, Marco,Barilli, Alessio,Lesma, Giordano,Passarella, Daniele,Riva, Sergio,Silvani, Alessandra,Danieli, Bruno
, p. 9525 - 9527 (2007/10/03)
Kinetic resolution of N-Boc-piperidine-2-ethanol (2), a case of remote stereocenter discrimination, was accomplished by sequential transesterification mediated by two enzymes, Lipase PS and porcine pancreatic lipase, showing opposite enantioselectivity. The gram-scale availability of the two enantiomeric N-Boc alcohols 2a (R) and 2c (S) enlarges their synthetic exploitation for the enantioselective preparation of piperidine alkaloids. As an example, the convenient three-step synthesis of both the enantiomers of sedamine and allosedamine is described.
Enantiospecific and stereoselective synthesis of (-)-allosedamine
Felpin, Fran?ois-Xavier,Lebreton, Jacques
, p. 225 - 227 (2007/10/03)
A total synthesis of (-)-allosedamine (>99% ee, de) is described in 14 steps with an overall yield of 29% from benzaldehyde.
