Synthetic applications of ortho esters
... In contrast to acetal derivatives of carbonyl compounds, ortho esters have found surprisingly limited use in organic synthesis [1]. Since ortho esters are among the few carboxylic acid protective groups that demonstrate a high level of stability toward strong nucleophiles and bases, most current app ...
... In contrast to acetal derivatives of carbonyl compounds, ortho esters have found surprisingly limited use in organic synthesis [1]. Since ortho esters are among the few carboxylic acid protective groups that demonstrate a high level of stability toward strong nucleophiles and bases, most current app ...
Study Guide Chapter 4 Alcohols and Alkyl Halides
... A chlorine at C-2 is on the opposite side of the ring from the C-1 hydroxyl group in trans2-chlorocyclopentanol. Note that it is not necessary to assign a number to the carbon that bears the hydroxyl group; naming the compound as a derivative of cyclopentanol automatically requires the hydroxyl grou ...
... A chlorine at C-2 is on the opposite side of the ring from the C-1 hydroxyl group in trans2-chlorocyclopentanol. Note that it is not necessary to assign a number to the carbon that bears the hydroxyl group; naming the compound as a derivative of cyclopentanol automatically requires the hydroxyl grou ...
Communications to the Editor - UCLA Chemistry and Biochemistry
... also be converted to a mixture in which 6b predominated by base treatment. We assumed that 6a and 6b are the endo (syn to carbonyl) and exo (anti to carbonyl) isomers, respectively. However, the correctness of this assignment was not proven until the completion of the synthesis when the synthetic pr ...
... also be converted to a mixture in which 6b predominated by base treatment. We assumed that 6a and 6b are the endo (syn to carbonyl) and exo (anti to carbonyl) isomers, respectively. However, the correctness of this assignment was not proven until the completion of the synthesis when the synthetic pr ...
E- Sedatives and Hypnotics Lectures
... The CNS depressant activity of chloral hydrate is assumed to be due to its in vivo metabolism to trichloroethanol. It is prepared by prolonged chlorination of ethanol, the final product is crystalline additive compound (Chloral alcoholate), which is collected, distilled with H2SO4 to yield which is ...
... The CNS depressant activity of chloral hydrate is assumed to be due to its in vivo metabolism to trichloroethanol. It is prepared by prolonged chlorination of ethanol, the final product is crystalline additive compound (Chloral alcoholate), which is collected, distilled with H2SO4 to yield which is ...
Free Radicals
... For free-radical α-bromination of a Boc glycine ester, see: Org. Synth. Coll., 9, 526 (1998). Both aliphatic and aromatic aldehydes are converted to acyl bromides under free-radical conditions: Tetrahedron Lett., 3809 (1979); Synlett, 347 (1990); Tetrahedron Lett., 31, 7237 (1990). In acetonitrile, ...
... For free-radical α-bromination of a Boc glycine ester, see: Org. Synth. Coll., 9, 526 (1998). Both aliphatic and aromatic aldehydes are converted to acyl bromides under free-radical conditions: Tetrahedron Lett., 3809 (1979); Synlett, 347 (1990); Tetrahedron Lett., 31, 7237 (1990). In acetonitrile, ...
Melt Modification of Poly(styrene-co-maleic anhydride)
... amide formation via in situ generated carboxylic acids as shown in Figure 1 (pathway b). Consequently, C11OXA addition converted free carboxylic acid. In order to quantify the anhydride conversion, the ANH1780 signal of the products is compared with the ANH1780 signal of the educt SMA17. For the bin ...
... amide formation via in situ generated carboxylic acids as shown in Figure 1 (pathway b). Consequently, C11OXA addition converted free carboxylic acid. In order to quantify the anhydride conversion, the ANH1780 signal of the products is compared with the ANH1780 signal of the educt SMA17. For the bin ...
CE4501 Environmental Engineering Chemical Processes
... to become protonated (and thus volatile and toxic). The possible forms of cyanide and CN-, HCN, and Ni(CN)42-. The possible forms of Ni in addition to the cyanide complex are Ni2+, NiOH+, Ni(OH)2o, Ni(OH)3-T. First, let’s calculate the concentration of HCN in the absence of Ni(II): CT = [HCN] + [CN- ...
... to become protonated (and thus volatile and toxic). The possible forms of cyanide and CN-, HCN, and Ni(CN)42-. The possible forms of Ni in addition to the cyanide complex are Ni2+, NiOH+, Ni(OH)2o, Ni(OH)3-T. First, let’s calculate the concentration of HCN in the absence of Ni(II): CT = [HCN] + [CN- ...
Energetics - chemistryatdulwich
... Uses of energy cycles: to test ionic and bonding models See table 13 in your IB data booklet which compares experimental values (obtained using Born-Haber) and theoretical values. If the experimental value is greater than the theoretical value calculated using electrostatic principles, this means th ...
... Uses of energy cycles: to test ionic and bonding models See table 13 in your IB data booklet which compares experimental values (obtained using Born-Haber) and theoretical values. If the experimental value is greater than the theoretical value calculated using electrostatic principles, this means th ...
Introduction to Coordination Chemistry
... ion is Zn2, the electron configuration is 3d10. Therefore, the 4s and 4p orbitals are empty and can be hybridized to give a set of four empty sp3 hybrid orbitals. This set of hybrid orbitals could accommodate four pairs of electrons donated by ligands with the bonds pointing toward the corners of a ...
... ion is Zn2, the electron configuration is 3d10. Therefore, the 4s and 4p orbitals are empty and can be hybridized to give a set of four empty sp3 hybrid orbitals. This set of hybrid orbitals could accommodate four pairs of electrons donated by ligands with the bonds pointing toward the corners of a ...
Chapter 1 – Reaction Kinetics Answer Key
... water will occur as water is formed in a reaction that occurs in aqueous solution. This is, of course, nonsense! As the entire reaction occurs in the solvent water, there will simply be a ...
... water will occur as water is formed in a reaction that occurs in aqueous solution. This is, of course, nonsense! As the entire reaction occurs in the solvent water, there will simply be a ...
Beyond Conventional N-Heterocyclic Carbenes
... multiple factors.18 Calculations suggest that C2 bonding and C4 bonding proceed via distinctly different reaction pathways involving either C2-H heterolytic bond cleavage or C4-H oxidative addition, implicating an iridium(V) species (see Scheme 2).19 Such mechanistic proposals were further supporte ...
... multiple factors.18 Calculations suggest that C2 bonding and C4 bonding proceed via distinctly different reaction pathways involving either C2-H heterolytic bond cleavage or C4-H oxidative addition, implicating an iridium(V) species (see Scheme 2).19 Such mechanistic proposals were further supporte ...
No Slide Title
... phenol reacts with sodium hydroxide to form a salt - sodium phenoxide it is ionic and water soluble C6H5OH(aq) + NaOH(aq) ——> C6H5O¯ Na+(aq) + H2O(l) ...
... phenol reacts with sodium hydroxide to form a salt - sodium phenoxide it is ionic and water soluble C6H5OH(aq) + NaOH(aq) ——> C6H5O¯ Na+(aq) + H2O(l) ...
isompp
... can attack from below, or above, the aldehyde. A mixture of the two enantiomers is formed. ...
... can attack from below, or above, the aldehyde. A mixture of the two enantiomers is formed. ...
Isomerism Guide
... can attack from below, or above, the aldehyde. A mixture of the two enantiomers is formed. ...
... can attack from below, or above, the aldehyde. A mixture of the two enantiomers is formed. ...
No Slide Title
... can attack from below, or above, the aldehyde. A mixture of the two enantiomers is formed. ...
... can attack from below, or above, the aldehyde. A mixture of the two enantiomers is formed. ...
d-Block chemistry: general considerations
... when the nuclear charge is 24 (the atomic number of Cr) and the interelectronic interaction energies for each of the [Ar]4s1 3d 5 and [Ar]4s2 3d 4 configurations. Fortunately, M2þ and M3þ ions of the first row d-block metals all have electronic configurations of the general form [Ar]3d n , and so the c ...
... when the nuclear charge is 24 (the atomic number of Cr) and the interelectronic interaction energies for each of the [Ar]4s1 3d 5 and [Ar]4s2 3d 4 configurations. Fortunately, M2þ and M3þ ions of the first row d-block metals all have electronic configurations of the general form [Ar]3d n , and so the c ...
Project Overview
... Professor William Tam received his B.Sc. at the University of Hong Kong in 1990 and his Ph.D. at the University of Toronto (Canada) in 1995. He was an NSERC postdoctoral fellow at the Imperial College (UK) and at Harvard University (USA). He joined the Department of Chemistry at the University of Gu ...
... Professor William Tam received his B.Sc. at the University of Hong Kong in 1990 and his Ph.D. at the University of Toronto (Canada) in 1995. He was an NSERC postdoctoral fellow at the Imperial College (UK) and at Harvard University (USA). He joined the Department of Chemistry at the University of Gu ...
Enzyme Catalysis.pptx
... • coordination of a ligand by a metal (as a Lewis acid) can also lead to polarisation of a ligand – e.g. pKa of metal-bound H2O is 7.2, making it easier to deprotonate, therby generating –OH as a nucleophile • for example, zinc-bound water in carbonic anhydrase, a highly efficient metalloenzyme a ...
... • coordination of a ligand by a metal (as a Lewis acid) can also lead to polarisation of a ligand – e.g. pKa of metal-bound H2O is 7.2, making it easier to deprotonate, therby generating –OH as a nucleophile • for example, zinc-bound water in carbonic anhydrase, a highly efficient metalloenzyme a ...
Monomer
... ⇒ -TiCl3 (brown color) was found to be effective for the polymerization (prepared by mixing TiCl4 with H2, aluminium, or alkylaluminiums Still isotacticity 20 – 40 % with Al(C2H5)2Cl -, -, -crystals of TiCl3 were found to increase the isoctacticity ...
... ⇒ -TiCl3 (brown color) was found to be effective for the polymerization (prepared by mixing TiCl4 with H2, aluminium, or alkylaluminiums Still isotacticity 20 – 40 % with Al(C2H5)2Cl -, -, -crystals of TiCl3 were found to increase the isoctacticity ...
Exam #3
... (12 pts) Bromoetherification, the addition of the elements Br and OR to a double bond, is a common method for constructing rings containing oxygen atoms. Draw a stepwise mechanism for the following INTRAMOLECULAR bromoetherification reaction. Hint: the mechanism is analogous to that of bromohydrin f ...
... (12 pts) Bromoetherification, the addition of the elements Br and OR to a double bond, is a common method for constructing rings containing oxygen atoms. Draw a stepwise mechanism for the following INTRAMOLECULAR bromoetherification reaction. Hint: the mechanism is analogous to that of bromohydrin f ...
Growth of Platinum Clusters in Solution and on Biopolymers: The
... based on the density functional theory [7–9]. However, the microscopic mechanism through which metal clusters form remains difficult to understand [10]. In particular, the elementary steps leading to the nucleation and growth of transition metal clusters upon chemical reduction of metal salts are, a ...
... based on the density functional theory [7–9]. However, the microscopic mechanism through which metal clusters form remains difficult to understand [10]. In particular, the elementary steps leading to the nucleation and growth of transition metal clusters upon chemical reduction of metal salts are, a ...
Hydroformylation
Hydroformylation, also known as oxo synthesis or oxo process, is an important homogeneously catalyzed industrial process for the production of aldehydes from alkenes. This chemical reaction entails the addition of a formyl group (CHO) and a hydrogen atom to a carbon-carbon double bond. This process has undergone continuous growth since its invention in 1938: Production capacity reached 6.6×106 tons in 1995. It is important because the resulting aldehydes are easily converted into many secondary products. For example, the resulting aldehydes are hydrogenated to alcohols that are converted to plasticizers or detergents. Hydroformylation is also used in specialty chemicals, relevant to the organic synthesis of fragrances and natural products. The development of hydroformylation, which originated within the German coal-based industry, is considered one of the premier achievements of 20th-century industrial chemistry.The process typically entails treatment of an alkene with high pressures (between 10 to 100 atmospheres) of carbon monoxide and hydrogen at temperatures between 40 and 200 °C. Transition metal catalysts are required.