HIGHLY SELECTIVE RHODIUM–CATALYZED C–H BORYLATIONS IN
... to alleviate the requirement for prefunctionalized molecules such as aryl halides to obtain these desired organoboron substrates. We report the first use of a rhodium N–heterocyclic carbene (NHC) complex for the catalytic C–H borylation. The reaction is found to proceed under very mild conditions (r ...
... to alleviate the requirement for prefunctionalized molecules such as aryl halides to obtain these desired organoboron substrates. We report the first use of a rhodium N–heterocyclic carbene (NHC) complex for the catalytic C–H borylation. The reaction is found to proceed under very mild conditions (r ...
Amino Acids and Proteins
... The 20 amino acids that occur naturally in proteins differ in the identity of the R group bonded to the α carbon. The R group is called the side chain of the amino acid. The simplest amino acid, called glycine, has R = H. All other amino acids (R ñ H) have a stereogenic center on the ` carbon. As is ...
... The 20 amino acids that occur naturally in proteins differ in the identity of the R group bonded to the α carbon. The R group is called the side chain of the amino acid. The simplest amino acid, called glycine, has R = H. All other amino acids (R ñ H) have a stereogenic center on the ` carbon. As is ...
幻灯片 1
... Bonding in organic compounds at that time was thought to be of either the water type, as in alcohols, ROH, or of the radical type, as in ethers which would be given the formula RO. But Williamson, by his ether synthesis, showed that mixed ethers, with two different alkyl groups, could be prepared. ...
... Bonding in organic compounds at that time was thought to be of either the water type, as in alcohols, ROH, or of the radical type, as in ethers which would be given the formula RO. But Williamson, by his ether synthesis, showed that mixed ethers, with two different alkyl groups, could be prepared. ...
Chapter 1 Chemical Bonding and Chemical Structure
... Acidity of Amines • NH3, RNH2, and R2NH are amphoteric: they may act as bases and acids • They are very weakly acidic – Will give up H+ to a very strong base • The conjugate base of an amine is called an amide (do not confuse with amide derivatives of carboxylic acids) ...
... Acidity of Amines • NH3, RNH2, and R2NH are amphoteric: they may act as bases and acids • They are very weakly acidic – Will give up H+ to a very strong base • The conjugate base of an amine is called an amide (do not confuse with amide derivatives of carboxylic acids) ...
Unit 2
... that is _ _ _ _ _ _ _ _ _ by an industrial process called _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _. To start with, liquid crude oil is fed into a _ _ _ _ _ _ where it is vaporized. The _ _ _ mixture of gases then passes into a fractionating _ _ _ _ _ _ and begins its journey upwards from the hott ...
... that is _ _ _ _ _ _ _ _ _ by an industrial process called _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _. To start with, liquid crude oil is fed into a _ _ _ _ _ _ where it is vaporized. The _ _ _ mixture of gases then passes into a fractionating _ _ _ _ _ _ and begins its journey upwards from the hott ...
Organic Chemistry II with Dr Roche
... Naming these heterocyclic compounds depends on the ring size and number of oxygens. (It can be confusing at first…) ...
... Naming these heterocyclic compounds depends on the ring size and number of oxygens. (It can be confusing at first…) ...
View/Open
... more being created daily, naming them all is a real problem. Part of the problem is due to the sheer complexity of organic structures, but part is also due to the fact that chemical names have more than one purpose. For Chemical Abstracts Service (CAS), which catalogs and indexes the worldwide chemi ...
... more being created daily, naming them all is a real problem. Part of the problem is due to the sheer complexity of organic structures, but part is also due to the fact that chemical names have more than one purpose. For Chemical Abstracts Service (CAS), which catalogs and indexes the worldwide chemi ...
13C NMR - Creighton Chemistry Webserver
... C NMR spectra normally are not integrated peak intensities can be used to guess the “type” of carbon: usually, CH3 > CH2 > CH > C ...
... C NMR spectra normally are not integrated peak intensities can be used to guess the “type” of carbon: usually, CH3 > CH2 > CH > C ...
Organic Chemistry with a Biological Emphasis Volume I
... Composed of the four elements carbon, hydrogen, oxygen and nitrogen, capsaicin is produced by the pepper plant for the purpose of warding off hungry mammals. The molecule binds to and activates a mammalian receptor protein called TrpV1, which in normal circumstances has the job of detecting high tem ...
... Composed of the four elements carbon, hydrogen, oxygen and nitrogen, capsaicin is produced by the pepper plant for the purpose of warding off hungry mammals. The molecule binds to and activates a mammalian receptor protein called TrpV1, which in normal circumstances has the job of detecting high tem ...
10 Haloalkanes and Haloarenes
... In the case of unsymmetrical alkenes, carbon atoms involved in double bond are non-equivalent, so the addition of HX in unsymmetrical alkene takes place according to Markownikoff’s rule. According to Markownikoff’s rule, “during addition of an unsymmetrical reagent across the double bond of an unsym ...
... In the case of unsymmetrical alkenes, carbon atoms involved in double bond are non-equivalent, so the addition of HX in unsymmetrical alkene takes place according to Markownikoff’s rule. According to Markownikoff’s rule, “during addition of an unsymmetrical reagent across the double bond of an unsym ...
Organic Chemistry Fifth Edition
... Geometry at N Hybridization of N in aniline lies between sp3 and sp2. Lone pair of N can be delocalized into ring best if N is sp2 and lone pair is in a p orbital. Lone pair bound most strongly by N if pair is in an sp3 orbital of N, rather than p. Actual hybridization is a compromise that maximize ...
... Geometry at N Hybridization of N in aniline lies between sp3 and sp2. Lone pair of N can be delocalized into ring best if N is sp2 and lone pair is in a p orbital. Lone pair bound most strongly by N if pair is in an sp3 orbital of N, rather than p. Actual hybridization is a compromise that maximize ...
Document
... • trans-Cyclooctene is the smallest isolable trans cycloalkene less stable than cis-cyclooctene, making it one of the few alkenes having a higher energy trans isomer. ...
... • trans-Cyclooctene is the smallest isolable trans cycloalkene less stable than cis-cyclooctene, making it one of the few alkenes having a higher energy trans isomer. ...
CHEMISTRY B- MOLES PACKET NAME: HR: ______ PAGE 1
... Elements generally exist as the particles we call atoms. A mole of carbon contains 6.02 x 1023 atoms of carbon. A mole of helium contains 6.02 x 1023 atoms of helium. A mole of sodium contains 6.02 x 1023 atoms of sodium. A mole of gold contains 6.02 x 1023 atoms of gold. However, we have learned ab ...
... Elements generally exist as the particles we call atoms. A mole of carbon contains 6.02 x 1023 atoms of carbon. A mole of helium contains 6.02 x 1023 atoms of helium. A mole of sodium contains 6.02 x 1023 atoms of sodium. A mole of gold contains 6.02 x 1023 atoms of gold. However, we have learned ab ...
chemistry worksheet # 2: the mole as a unit of mass
... Elements generally exist as the particles we call atoms. A mole of carbon contains 6.02 x 1023 atoms of carbon. A mole of helium contains 6.02 x 1023 atoms of helium. A mole of sodium contains 6.02 x 1023 atoms of sodium. A mole of gold contains 6.02 x 1023 atoms of gold. However, we have learned ab ...
... Elements generally exist as the particles we call atoms. A mole of carbon contains 6.02 x 1023 atoms of carbon. A mole of helium contains 6.02 x 1023 atoms of helium. A mole of sodium contains 6.02 x 1023 atoms of sodium. A mole of gold contains 6.02 x 1023 atoms of gold. However, we have learned ab ...
THE DIFFUSION MECHANISM OF HYDROCARBONS IN... Jirong Xiao B.S., East China Institute of Chemical Technology
... The primary building block of the zeolite structure is a tetrahedron of four oxygen atoms surrounding a central silicon atom. The tetrahedrons are bonded together via shared oxygen atoms to form a variety of secondary building units, which in turn generate a wide range of polyhedra. The combination ...
... The primary building block of the zeolite structure is a tetrahedron of four oxygen atoms surrounding a central silicon atom. The tetrahedrons are bonded together via shared oxygen atoms to form a variety of secondary building units, which in turn generate a wide range of polyhedra. The combination ...
Aromaticity
In organic chemistry, the term aromaticity is formally used to describe an unusually stable nature of some flat rings of atoms. These structures contain a number of double bonds that interact with each other according to certain rules. As a result of their being so stable, such rings tend to form easily, and once formed, tend to be difficult to break in chemical reactions. Since one of the most commonly encountered aromatic system of compounds in organic chemistry is based on derivatives of the prototypical aromatic compound benzene (common in petroleum), the word “aromatic” is occasionally used to refer informally to benzene derivatives, and this is how it was first defined. Nevertheless, many non-benzene aromatic compounds exist. In living organisms, for example, the most common aromatic rings are the double-ringed bases in RNA and DNA.The earliest use of the term “aromatic” was in an article by August Wilhelm Hofmann in 1855. Hofmann used the term for a class of benzene compounds, many of which do have odors (unlike pure saturated hydrocarbons). Today, there is no general relationship between aromaticity as a chemical property and the olfactory properties of such compounds, although in 1855, before the structure of benzene or organic compounds was understood, chemists like Hofmann were beginning to understand that odiferous molecules from plants, such as terpenes, had chemical properties we recognize today are similar to unsaturated petroleum hydrocarbons like benzene.In terms of the electronic nature of the molecule, aromaticity describes the way a conjugated ring of unsaturated bonds, lone pairs of electrons, or empty molecular orbitals exhibit a stabilization stronger than would be expected by the stabilization of conjugation alone. Aromaticity can be considered a manifestation of cyclic delocalization and of resonance. This is usually considered to be because electrons are free to cycle around circular arrangements of atoms that are alternately single- and double-bonded to one another. These bonds may be seen as a hybrid of a single bond and a double bond, each bond in the ring identical to every other. This commonly seen model of aromatic rings, namely the idea that benzene was formed from a six-membered carbon ring with alternating single and double bonds (cyclohexatriene), was developed by August Kekulé (see History section below). The model for benzene consists of two resonance forms, which corresponds to the double and single bonds superimposing to produce six one-and-a-half bonds. Benzene is a more stable molecule than would be expected without accounting for charge delocalization.