Linked Life Data

15136811

Source:http://linkedlifedata.com/resource/pubmed/id/15136811

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2004-5-11
pubmed:abstractText
Insight in the steric and electronic parameters governing isomerization processes in artificial molecular motors is essential in order to design more advanced motor systems. A subtle balance of steric parameters and the combination of helical and central chirality are key features of light-driven unidirectional rotary molecular motors constructed so far. In an approach to decrease the steric hindrance around the central olefinic bond (rotary axis) and thereby lowering the energy barrier for helix inversion resulting in an increased rotation rate, the boundaries of our molecular motor design are explored. In a new design of a light-driven molecular motor based on a sterically overcrowded alkene the methyl substituent adjacent to the stereogenic center, which is responsible for the control of the direction of rotation, is shifted one position away from the fjord region of the molecule compared to the second-generation motor systems. In contrast to previously developed light-driven molecular motors, there is a preference for the methyl substituent to adopt a pseudo-equatorial orientation. Nevertheless, this new type of motor is capable of functioning as a rotary molecular motor, albeit not with full unidirectionality. Under the combined influence of light and heat, there is a preferred clockwise rotation of one half of the molecule. Surprisingly, the effect of shifting the methyl substituent on the energy barrier for helix inversion is small and even a slight increase in the barrier is observed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1477-0520
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
2
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1531-41
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:15136811-Alkenes, pubmed-meshheading:15136811-Circular Dichroism, pubmed-meshheading:15136811-Crystallography, X-Ray, pubmed-meshheading:15136811-Cyclization, pubmed-meshheading:15136811-Heterocyclic Compounds, 3-Ring, pubmed-meshheading:15136811-Hot Temperature, pubmed-meshheading:15136811-Hydrazones, pubmed-meshheading:15136811-Isomerism, pubmed-meshheading:15136811-Light, pubmed-meshheading:15136811-Models, Molecular, pubmed-meshheading:15136811-Molecular Conformation, pubmed-meshheading:15136811-Naphthalenes, pubmed-meshheading:15136811-Nitriles, pubmed-meshheading:15136811-Photochemistry, pubmed-meshheading:15136811-Piperidines, pubmed-meshheading:15136811-Rotation, pubmed-meshheading:15136811-Spectrophotometry, Ultraviolet, pubmed-meshheading:15136811-Stereoisomerism, pubmed-meshheading:15136811-Sulfhydryl Compounds, pubmed-meshheading:15136811-Sulfur Compounds, pubmed-meshheading:15136811-Thermodynamics
pubmed:year
2004
pubmed:articleTitle
Exploring the boundaries of a light-driven molecular motor design: new sterically overcrowded alkenes with preferred direction of rotation.
pubmed:affiliation
Department of Organic and Molecular Inorganic Chemistry Stratingh Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
pubmed:publicationType
Journal Article