Results 41 to 50 of about 1,879 (233)
Acta Crystallographica Section E, 2014 In the title compounds, C22H20N2O4S, (I), and C22H19ClN2O4S, (II), the pyrrolidine rings have twist conformations on the spiro–spiro C—C bonds. In (I), the five-membered ring of the oxindole moiety has an envelope conformation with the spiro C atom as ...
M. P. Savithri +5 more
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Acta Crystallographica Section E: Crystallographic Communications, 2015 The title compound, C23H22N2O4S, crystallized with two independent molecules (A and B) in the asymmetric unit. They have very similar conformations with the pyrrolidine ring having a twisted conformation, on the Cspiro—Cspiro bond, in both molecules.
R. Raja +4 more
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Research on chemical intermediates (Print), 2023 In this research, the starting compounds tetrachloromonospirocyclotriphosphazenes, (BzSpiro-5)R^1(N_3P_3)Cl_4 [Bz: Benzyl; R^1: Me ( 1 ) and R^1: Et ( 2 )], were synthesized from the reactions of hexachlorocyclotriphosphazene, N_3P_3Cl_6 ( HCCP , trimer)
Reşit Cemaloğlu +7 more
semanticscholar +1 more source
The Diarylprolinol Silyl Ethers: After 20 Years Still Opening New Doors in Asymmetric Catalysis
Angewandte Chemie, Volume 138, Issue 11, 9 March 2026.Catalysis Rules! The year 2025 marks the 20th anniversary of diarylprolinol silyl ethers in asymmetric organocatalysis. During the first decade after their discovery, these catalysts have been established as one of the most versatile tools in aminocatalysis. Although now considered mature, recent years have witnessed renewed innovation.
Enrico Marcantonio +2 more
wiley +2 more sources
Langgestreckte Moleküle von Dispiro[5.1.5.2]‐Typ
Chemische Berichte, 1992 Rod‐Like Dispiro[5.1.5.2] CompoundsA number of symmetrically and unsymmetrically substituted spiro compounds were synthesized starting from the dispiro[5.1.5.2]trione 1. The trans‐trans isomers of 2, 3, 6–10, and 11 were separated from the cis‐cis and cis‐trans isomers.
Vögtle, F., Hartmann, R., Boettcher, J.
openaire +2 more sources
Dispiro[fluorene-9,5′-[1,2,3,4]tetrathiane-6′,9′′-fluorene] [PDF]
Acta Crystallographica Section C Crystal Structure Communications, 2001 The tetrathiane ring of the title compound, C26H16S4, has a chair conformation and the molecule has approximate C2 symmetry. Each of the two fluorene ring systems is virtually planar, with the ring planes intersecting at an angle of 67.58 (5)°. This novel compound has been formed as a side product from the treatment of 9H-fluorene-9-thione with methyl ...
Linden, Anthony +2 more
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Scientific Reports, 2022 A series of 1″-(alkylsulfonyl)-dispiro[indoline-3,2′-pyrrolidine-3′,3″-piperidine]-2,4″-diones 6a‒o has been synthesized through regioselective multi-component azomethine dipolar cycloaddition reaction of 1-(alkylsulfonyl)-3,5-bis(ylidene)-piperidin-4 ...
Nehmedo G. Fawazy +13 more
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, 2016 Dispiro-1,2,4,5-tetraoxanes via Ozonolysis of Cycloalkanone O-Methyl Oximes: A Comparison with the Peroxidation of Cycloalkanones in Acetonitrile−Sulfuric Acid ...
Yuxiang Dong (1377870) +1 more
core +1 more source
Beilstein Journal of Organic Chemistry, 2016 An effective and highly regio- and diastereoselective one-pot method for the synthesis of new polynuclear dispiroheterocyclic systems with five stereogenic centers (dispiro[imidazo[4,5-e]thiazolo[3,2-b]-1,2,4-triazine-6,3′-pyrrolidine-2′,3′′-indoles ...
Alexei N. Izmest’ev +9 more
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Synthesis of 1-azaspiro[4.4]nonan-1-oxyls via intramolecular 1,3-dipolar cycloaddition
Beilstein Journal of Organic Chemistry, 2019 Sterically shielded nitroxides of the pyrrolidine series have shown the highest resistance to reduction. Here we report the synthesis of new pyrrolidine nitroxides from 5,5-dialkyl-1-pyrroline N-oxides via the introduction of a pent-4-enyl group to the ...
Yulia V. Khoroshunova +5 more
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