نتایج جستجو برای: 18 and 24 crown ethers

تعداد نتایج: 16918122  

Journal: :Journal of inclusion phenomena and macrocyclic chemistry 2021

Abstract Crown ethers containing an acridone or acridine unit are successfully applied opto- and electrochemical cation sensors. The heteroaromatic of these macrocycles can be in different forms during the applications, which have a strong influence on sensing behavior. Moreover, case acridono-macrocycles prototropic equilibrium takes place upon complexation, is effected by physicochemical char...

2008
Geraldo M. de Lima James L. Wardell William T. A. Harrison

The asymmetric unit of the title compound, C(20)H(24)O(6), contains two mol-ecules that are identical within standard deviations concerning bond lengths and angles as well as their conformations. In the crystal structure, weak C-H⋯O inter-actions help to consolidate the packing.

2010
Anissa Mansour Mohamed Salah Belkhiria Jean-Claude Daran Habib Nasri

The asymmetric unit of the title compound, [Co(C(44)H(28)N(4))]·C(12)H(24)O(6), contains one half of a Co(II)(TPP) (TPP is tetra-phenyl-porphyrin) complex and one half of an 18-crown-6 mol-ecule of crystallization, both lying on inversion centers. The Co(II)(TPP) complex exhibits a nearly planar conformation of the porphyrinate core [maximum deviation = 0.069 (2) Å] with an average Co-N distanc...

2012
Tobias Grassl Markus Hamberger Nikolaus Korber

The title compound, C(2)H(2)·C(12)H(24)O(6)·2NH(3), was formed by co-crystallization of 18-crown-6 and acetyl-ene in liquid ammonia. The 18-crown-6 mol-ecule has threefold rotoinversion symmetry. The acteylene mol-ecule lies on the threefold axis and the whole mol-ecule is generated by an inversion center. The two ammonia mol-ecules are also located on the threefold axis and are related by inve...

Journal: :Acta Crystallographica Section E Structure Reports Online 2008

Journal: :Organic & biomolecular chemistry 2014
G Pazos M Pérez Z Gándara G Gómez Y Fall

An efficient procedure for preparing enantiopure polycyclic ethers is reported. The protocol is based on the photo-oxidation/conjugate addition sequence over a chiral functionalized furan, which was prepared from commercially available tri-O-acetyl-D-glucal. The Michael addition step afforded two products with the same absolute configuration from a mixture of diastereomers.

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید