In the twilight zone between [2]pseudorotaxanes and [2]rotaxanes

Chemistry - A European Journal

Volumn 9, Issue 19, 2003, Pages 4611-4625

  Jeppesen, Jan O ^a,b   Vignon, Scott A ^a   Stoddart, J Fraser ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

^b UNIVERSITY OF SOUTHERN DENMARK   (Denmark)

Author keywords

Electrochemistry; Kinetics; Rotaxanes; Self assembly; Supramolecular chemistry

Indexed keywords

ENTHALPY; FREE ENERGY; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; SELF ASSEMBLY;

DIFFERENTIAL PULSE VOLTAMMETRY;

ORGANIC COMPOUNDS;

1,5 DIOXYNAPHTHALENE; CYCLOBIS(PARAQUAT 4 PHENYLENE); CYCLOPHANE; METHYL GROUP; NAPHTHALENE DERIVATIVE; PARAQUAT; PSEUDOROTAXANE DERIVATIVE; PYRROLOTETRATHIAFULVALENE; ROTAXANE; TAXANE DERIVATIVE; TETRATHIAFULVALENE DERIVATIVE; THIOL DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; CHROMATOGRAPHY; COLOR; DIFFERENTIAL PULSE VOLTAMMETRY; ELECTROCHEMISTRY; ENERGY; ENTHALPY; ENTROPY; KINETICS; MOLECULAR INTERACTION; MOLECULAR RECOGNITION; PROTON NUCLEAR MAGNETIC RESONANCE; ROOM TEMPERATURE; SUPRAMOLECULAR CHEMISTRY; ULTRAVIOLET SPECTROSCOPY;

ELECTROCHEMISTRY; KINETICS; MAGNETIC RESONANCE SPECTROSCOPY; MODELS, MOLECULAR; MOLECULAR CONFORMATION; PARAQUAT; ROTAXANES; SPECTROPHOTOMETRY, ULTRAVIOLET; TEMPERATURE; THERMODYNAMICS;

EID: 0142074879     PISSN: 09476539     EISSN: None     Source Type: Journal    
DOI: 10.1002/chem.200304798     Document Type: Article

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117. For further details, see the Experimental Section.
118. 4+ ring has previously been observed in both bistable [2]rotaxanes and [2]pseudorotaxanes incorporating an MPTTF unit and a DNP moiety on the rod-section of its dumbbell component, see: ref. [13b].
119. 4+, but the ε value for this interaction is normally very weak at wavelengths higher than 700 nm.
120. -1.
121. 4+ ring. Such an SMe group resonates at a chemical shift higher than δ 2.6, whereas an "uncomplexed" SMe group has a chemical shift of about δ 2.40 ppm. See: a) ref. [13]; b) ref. [16].
122. See Supporting Information.
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125. c) ref. [15a]
126. 4+, respectively.
127. K. J. Laidler, Chemical Kinetics, Harper Collins Publisher, New York, 1987.
128. 0 is the initial absorbance (at 520 nm). This outcome is a consequence of the fact that the data points were collected in the early stage of the experiments where the reverse process is not yet occurring to any significant extent.
129. B is the Boltzmann constant.
130. 4+.
131. 4+, respectively, and t the time.
132. 3 at 300 K.
133. ≠ values would be expected to be small.
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138. 4+ is only 35 %.
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141. 4+.
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144. 4+ has almost a "constant" absorbance at 400 nm.
145. 1H NMR spectrum.
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