Photochemical reactions of diazodihydronaphthalenonesThese compounds are often referred to as naphthoquinone diazides in the literature. in cyclic ethers

Zhang, Wei; Shao, Xiangfeng; Yang, Li; Liu, Zhongli; Chow, Yuan L.

doi:10.1039/b106968n

Cited by 12 publications

(3 citation statements)

References 15 publications

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“…In compounds 11 and 12 , the overlap of the aromatic systems is immediately apparent, being approximately the same in the both molecules (Figure 3, left column). A similar molecular shape has been found in the macrocycles that incorporate hydroquinol,12 or biphenyl units bridged by the oxyethylene chains of the same length,13 while in the case of the anthracene backbone the elongated shape of the molecule is distorted 14. In compound 13 , the parallel arrangement of the fluorenone units is retained; however, one of them is considerably displaced with respect to the other in order to optimize the dipole–dipole interactions between the carbonyl groups.…”

Section: Resultssupporting

confidence: 54%

Bis(oxofluorenediyl)oxacyclophanes: Synthesis, Crystal Structure and Complexation with Paraquat in the Gas Phase

Luk’yanenko

Kirichenko

Lyapunov

et al. 2004

Chemistry A European J

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The first three representatives of the new family of oxacyclophanes incorporating two 2,7-dioxyfluorenone fragments, connected by [-CH(2)CH(2)O-](m) spacers (m=2-4), have been synthesized. The yield of the smallest oxacyclophane (m=2) is considerably higher with respect to the larger ones (m=3 and m=4), which are formed in comparable yields. Molecular modeling and NMR spectra analysis of the model compounds suggest that an essential difference in oxacyclophanes yields is caused by formation of quasi-cyclic intermediates, which are preorganized for macrocyclization owing to intramolecular pi-pi stacking interactions between the fluorenone units. The solid-state structures of these oxacyclophanes exhibit intra- and intermolecular pi-pi stacking interactions that dictate their rectangular shape in the fluorenone backbone and crystal packing of the molecules with the parallel or T-shape arrangement. The crystal packing in all cases is also sustained by weak C--HO hydrogen bonds. FAB mass spectral analysis of mixtures of the larger oxacyclophanes (m=3 and m=4) and a paraquat moiety revealed peaks corresponding to the loss of one and two PF(6) (-) counterions from the 1:1 complexes formed. However, no signals were observed for complexes of the paraquat moiety with the smaller oxacyclophane (m=2). Computer molecular modeling of complexes revealed a pseudorotaxane-like incorporation of the paraquat unit, sandwiched within a macrocyclic cavity between the almost parallel-aligned fluorenone rings of the larger oxacyclophanes (m=3 and m=4). In contrast to this, only external complexes of the smallest oxacyclophane (m=2) with a paraquat unit have been found in the energy window of 10 kcal mol(-1).

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Section: Resultssupporting

confidence: 54%

Bis(oxofluorenediyl)oxacyclophanes: Synthesis, Crystal Structure and Complexation with Paraquat in the Gas Phase

Luk’yanenko

Kirichenko

Lyapunov

et al. 2004

Chemistry A European J

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“…The overall conformations and molecular dimensions of these two diazacrown ethers are quite similar to those of the corresponding crown[6] compounds in the crystal state 17. 18 The peculiar rectangular shape of 8 , with the two phenyl rings perpendicular to the macrocycle average plane, is closely mirrored by the structure of a naphthoquinone‐based crown ether, namely the bis(2‐methyl‐1,4‐ naphthylene)‐22‐crown[6] 19…”

Section: Methodsmentioning

confidence: 93%

“…[17,18] The peculiar rectangular shape . [19] Geometrical considerations suggest that among the synthesized dibenzo macrocycles, diazacrown 6 is the most promising candidate for complexation of a metal ion such as a silver cation.…”

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confidence: 99%

Azacrown Ethers from Mustard Carbonate Analogues

et al. 2014

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Polycondensation of a nitrogen mustard carbonate analogue with aromatic diols under dilution conditions affords a series of azacrowns previously not easily accessible as they require multistep synthesis including protection, purification, cyclization and methylation. This novel synthesis relies upon the anchimeric effect of the nitrogen mustard carbonate and it does not require the use of any base

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Medium‐Sized Rings versus Macrocycles through Rhodium‐Catalyzed Ring‐Expansion Reactions of Cyclic Acetals

Ballesteros‐Garrido¹,

Rix²,

Besnard³

et al. 2012

Chemistry A European J

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α-Diazo β-ketoesters and diketones react with cyclic acetals under Rh(II) catalysis to yield unprecedented polyoxygenated 8- and 9-membered rings in one pot. The reactions occur under mild conditions with yields up to 90%. A perfect regioselectivity is obtained, which can be rationalized through a mechanistic hypothesis that considers 1) the formation of an oxonium ylide, 2) its transformation into an unsaturated acyclic oxocarbenium electrophilic intermediate, and 3) an intramolecular nucleophilic attack in a direct application of Baldwin's rules.

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Photochemical reactions of diazodihydronaphthalenonesThese compounds are often referred to as naphthoquinone diazides in the literature. in cyclic ethers

Cited by 12 publications

References 15 publications

Bis(oxofluorenediyl)oxacyclophanes: Synthesis, Crystal Structure and Complexation with Paraquat in the Gas Phase

Bis(oxofluorenediyl)oxacyclophanes: Synthesis, Crystal Structure and Complexation with Paraquat in the Gas Phase

Azacrown Ethers from Mustard Carbonate Analogues

Medium‐Sized Rings versus Macrocycles through Rhodium‐Catalyzed Ring‐Expansion Reactions of Cyclic Acetals

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