159898-10-9Relevant articles and documents
Synthesis of Azocanes from Piperidines via an Azetidinium Intermediate
Leverenz, Malte,Masson, Guillaume,Pardo, Domingo Gomez,Cossy, Janine
, p. 16325 - 16328 (2021/10/25)
α-Trifluoromethyl azocanes are accessible from 2-(trifluoropropan-2-ol) piperidines by metal-free ring-expansion involving a bicyclic azetidinium intermediate. The opening of the azetidinium intermediate was achieved by various nucleophiles (amines, alcoholates, carboxylates, phosphonates, halides and pseudo-halides) with an excellent regio- diastereo- and enantioselectivity and in good yields. The relative configuration of the piperidines and azocanes were assigned and the deprotected azocanes offer opportunities for further derivatization.
Gram-Scale Synthesis of the (?)-Sparteine Surrogate and (?)-Sparteine
Firth, James D.,Canipa, Steven J.,Ferris, Leigh,O'Brien, Peter
supporting information, p. 223 - 226 (2017/12/29)
An 8-step, gram-scale synthesis of the (?)-sparteine surrogate (22 % yield, with just 3 chromatographic purifications) and a 10-step, gram-scale synthesis of (?)-sparteine (31 % yield) are reported. Both syntheses proceed with complete diastereocontrol and allow access to either antipode. Since the syntheses do not rely on natural product extraction, our work addresses long-term supply issues relating to these widely used chiral ligands.
Enzymatic resolution of cyclic N-Boc protected β-aminoacids
Pousset, Cyrille,Callens, Roland,Haddad, Mansour,Larcheveque, Marc
, p. 3407 - 3412 (2007/10/03)
Methyl and ethyl esters of N-Boc homoproline, homopipecolic acid and 3-carboxymethyl-morpholine were kinetically resolved by hydrolysis catalysed by Burkholderia cepacia lipase to give the corresponding acids and residual esters in enantiomeric excesses better than 99% (E > 100).
Complementary Enantioselective Approaches to the Quinolizidine Alkaloids Lupinine and Epilupinine by Enolate Claisen Rearrangements or Direct Allylation of Piperidin-2-ylacetic Acid Derivatives
Morley, Christopher,Knight, David W.,Share, Andrew C.
, p. 2903 - 2908 (2007/10/02)
Enolate Claisen rearrangement of the piperidinylacetic acid allyl ester 11 leads mainly to the diastereoisomer 12, whereas direct allylation of the lithio enolate of the corresponding methyl ester 14 gives a preponderance of the alternative diastereoisomer 13.Hydroboration and cyclisation of the latter isomer has been used to obtain (+)-lupinine 17; this approach is adaptable to the synthesis of either enantiomer of both lupinine and epilupinine, given the correct choice of C-allylation method.
