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Carbon Nanohoop
Carbon nanohoops are a class of molecules consisting of aromatic sections curved out of planarity by the inherent cyclic geometry of the molecule. This class of molecules came into existence with the synthesis of cycloparaphenylenes by Ramesh Jasti in the lab of Carolyn Bertozzi and since then has been expanded into cyclonaphthylenes, cyclochrysenylenes, and even cyclohexabenzocoronenylenes. Moreover, several nanohoops containing such antiaromatic units as dibenzo ,eentalene and pyrrolo ,2-byrrole are reported. Carbon nanohoops often map on to a certain chirality of carbon nanotube. If the diameter is adequate, these molecules can host a fullerene A fullerene is an allotrope of carbon whose molecule consists of carbon atoms connected by single and double bonds so as to form a closed or partially closed mesh, with fused rings of five to seven atoms. The molecule may be a hollow sphere, .... For example, 0ycloparaphenylene can host a C60 fullerene. References Cyclophanes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycloparaphenylenes
A cycloparaphenylene is a molecule that consists of several benzene rings connected by covalent bonds in the para positions to form a hoop- or necklace-like structure. Its chemical formula is or Such a molecule is usually denoted 'n''PP where ''n'' is the number of benzene rings. A cycloparaphenylene can be considered as the smallest possible armchair carbon nanotube, and is a type of carbon nanohoop. Cycloparaphenylenes are challenging targets for chemical synthesis due to the ring strain incurred from forcing benzene rings out of planarity. History In 1934 by V. C. Parekh and P. C. Guha described the first published attempt to synthesize a cycloparaphenylene, specifically PP. They connected two aromatic rings with a sulfide bridge, and hoped that removal of the latter would yield the desired compound. However, the attempt failed as the compound would have been far too strained to exist under anything but extreme conditions. By 1993, Fritz Vögtle attempted to sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ramesh Jasti
Ramesh Jasti is a professor of organic chemistry at the University of Oregon. He was the first person to synthesize the elusive cycloparaphenylene in 2008 during post doctoral work in the laboratory of Professor Carolyn Bertozzi. He started his laboratory at Boston University where he was the recipient of the NSF CAREER award. His early lab repeatedly broke the record for the synthesis of the smallest cycloparaphenylene known. In 2014, he moved his laboratory to the University of Oregon where he expanded his focus to apply the molecules he discovered in the areas of organic materials, mechanically interlocked molecules, and biology. He is the Associate Director of the Materials Science Institute at the University of Oregon. Awards and honors * Fred Morrison Scholarship (1994) * Thieme Journal Award (2012) * American Chemical Society Young Academic Investigator Award (2013) * Boston University Ignition Award (2013) * Boston University Materials Science and Engineering Innovation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carolyn Bertozzi
Carolyn Ruth Bertozzi (born October 10, 1966) is an American chemist and Nobel laureate, known for her wide-ranging work spanning both chemistry and biology. She coined the term "bioorthogonal chemistry" for chemical reactions compatible with living systems. Her recent efforts include synthesis of chemical tools to study cell surface sugars called glycans and how they affect diseases such as cancer, inflammation, and viral infections like COVID-19. At Stanford University, she holds the Anne T. and Robert M. Bass Professorship in the School of Humanities and Sciences. Bertozzi is also an Investigator at the Howard Hughes Medical Institute (HHMI) and is the former Director of the Molecular Foundry, a nanoscience research center at Lawrence Berkeley National Laboratory. She received the MacArthur "genius" award at age 33. In 2010, she was the first woman to receive the prestigious Lemelson-MIT Prize faculty award. She is a member of the National Academy of Sciences (2005), th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Nanotube
A scanning tunneling microscopy image of a single-walled carbon nanotube Rotating single-walled zigzag carbon nanotube A carbon nanotube (CNT) is a tube made of carbon with diameters typically measured in nanometers. ''Single-wall carbon nanotubes'' (''SWCNTs'') are one of the allotropes of carbon, intermediate between fullerene cages and flat graphene, with diameters in the range of a nanometre. Although not made this way, single-wall carbon nanotubes can be idealized as cutouts from a two-dimensional hexagonal lattice of carbon atoms rolled up along one of the Bravais lattice vectors of the hexagonal lattice to form a hollow cylinder. In this construction, periodic boundary conditions are imposed over the length of this roll-up vector to yield a helical lattice of seamlessly bonded carbon atoms on the cylinder surface. ''Multi-wall carbon nanotubes'' (''MWCNTs'') consisting of nested single-wall carbon nanotubes weakly bound together by van der Waals interactions in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fullerene
A fullerene is an allotrope of carbon whose molecule consists of carbon atoms connected by single and double bonds so as to form a closed or partially closed mesh, with fused rings of five to seven atoms. The molecule may be a hollow sphere, ellipsoid, tube, or many other shapes and sizes. Graphene (isolated atomic layers of graphite), which is a flat mesh of regular hexagonal rings, can be seen as an extreme member of the family. Fullerenes with a closed mesh topology are informally denoted by their empirical formula C''n'', often written C''n'', where ''n'' is the number of carbon atoms. However, for some values of ''n'' there may be more than one isomer. The family is named after buckminsterfullerene (C60), the most famous member, which in turn is named after Buckminster Fuller. The closed fullerenes, especially C60, are also informally called buckyballs for their resemblance to the standard ball of association football ("soccer"). Nested closed fullerenes have been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
