Nucleophilic Substitution and b
... Task: convert to a staggered structure wherein H and Br are anti and predict product. We will convert to a Newman and see what we get… Ph ...
... Task: convert to a staggered structure wherein H and Br are anti and predict product. We will convert to a Newman and see what we get… Ph ...
Review
... Reactions with Carbanions Again, a negative charge at the allylic or benzylic position is much more stable than it would be in a lot of other positions. We’ve seen carbanions before in the form of Grignards or organolithiums. In those cases, we could show the carbon-metal bond as either covalent or ...
... Reactions with Carbanions Again, a negative charge at the allylic or benzylic position is much more stable than it would be in a lot of other positions. We’ve seen carbanions before in the form of Grignards or organolithiums. In those cases, we could show the carbon-metal bond as either covalent or ...
O R` R
... • HCN adds to aldehydes and ketones to form cyanohydrins. • The reaction is usually done in basic soln (pH 9-10) so that both CN– and HCN are present. O HC ...
... • HCN adds to aldehydes and ketones to form cyanohydrins. • The reaction is usually done in basic soln (pH 9-10) so that both CN– and HCN are present. O HC ...
Alcohols and Phenols
... • Can be more or less acidic than phenol itself • An electron-withdrawing substituent makes a phenol more acidic by delocalizing the negative charge • Phenols with an electron-donating substituent are less acidic because these substituents concentrate the charge ...
... • Can be more or less acidic than phenol itself • An electron-withdrawing substituent makes a phenol more acidic by delocalizing the negative charge • Phenols with an electron-donating substituent are less acidic because these substituents concentrate the charge ...
Some uses of mischmetall in organic synthesis
... absence of nickel diiodide (entry 3). It was thus anticipated that esters should behave like this unstrained lactone. This was confirmed: good yields in tertiary alcohols were obtained in both procedures (entries 4-6). Thus, with ε-caprolactone and esters the catalytic Barbier procedure does ...
... absence of nickel diiodide (entry 3). It was thus anticipated that esters should behave like this unstrained lactone. This was confirmed: good yields in tertiary alcohols were obtained in both procedures (entries 4-6). Thus, with ε-caprolactone and esters the catalytic Barbier procedure does ...
nucleophilic addition on ketones and ketimines - ISI
... The asymmetric allylation of ketones was also recently studied by the groups of Shibasaki22 and Yamamoto23 using soft transition metal–chiral diphosphine complexes as catalysts (Scheme 9). Shibasaki et al. used allyl boronates as nucleophiles for the allyl transfer on aliphatic and aromatic ketones ...
... The asymmetric allylation of ketones was also recently studied by the groups of Shibasaki22 and Yamamoto23 using soft transition metal–chiral diphosphine complexes as catalysts (Scheme 9). Shibasaki et al. used allyl boronates as nucleophiles for the allyl transfer on aliphatic and aromatic ketones ...
Alcohols and Phenols
... • Can be more or less acidic than phenol itself • An electron-withdrawing substituent makes a phenol more acidic by delocalizing the negative charge • Phenols with an electron-donating substituent are less acidic because these substituents concentrate the charge ...
... • Can be more or less acidic than phenol itself • An electron-withdrawing substituent makes a phenol more acidic by delocalizing the negative charge • Phenols with an electron-donating substituent are less acidic because these substituents concentrate the charge ...
Aromatic Compounds
... Rings: The Friedel-Crafts Reaction Alkylation • The introduction of an alkyl group onto the benzene ring • Called the Friedel-Crafts reaction after its discoverers • Among the most useful electrophilic aromatic substitution ...
... Rings: The Friedel-Crafts Reaction Alkylation • The introduction of an alkyl group onto the benzene ring • Called the Friedel-Crafts reaction after its discoverers • Among the most useful electrophilic aromatic substitution ...
Dehydration of n-propanol and methanol to produce
... Substrate conversion and DPE yields & selectivity information is depicted in Figure 1. According to Figure 1A, the conversion clearly increased with increasing temperature for all the catalysts tested. Sulfuric acid clearly resulted in higher substrate conversions as compared to the other two cataly ...
... Substrate conversion and DPE yields & selectivity information is depicted in Figure 1. According to Figure 1A, the conversion clearly increased with increasing temperature for all the catalysts tested. Sulfuric acid clearly resulted in higher substrate conversions as compared to the other two cataly ...
lecture 2 - alcohols-ethers
... SN1 reaction is a substitution reaction in organic chemistry. "SN" stands for nucleophilic substitution and the "1" represents the fact that the rate-determining step is unimolecular. ...
... SN1 reaction is a substitution reaction in organic chemistry. "SN" stands for nucleophilic substitution and the "1" represents the fact that the rate-determining step is unimolecular. ...
Chapter 23 SG5e
... (b) How do you account for the fact that the -COOH group of the conjugate acid of alanine is a stronger acid than the -COOH group of propanoic acid? The -NH3+ group is electron-withdrawing, so the adjacent -COOH group is made more acidic by an inductive effect. This situation is analogous to the ele ...
... (b) How do you account for the fact that the -COOH group of the conjugate acid of alanine is a stronger acid than the -COOH group of propanoic acid? The -NH3+ group is electron-withdrawing, so the adjacent -COOH group is made more acidic by an inductive effect. This situation is analogous to the ele ...
Richard R. Schrock - Nobel Lecture
... ering the likely synthetic difficulties associated with R being a 2,6-di-tbutylphenyl group, we settled on the 2,6-diisopropylphenyl group, a choice that in part was in response to a comment by K. B. Sharpless concerning the value of isopropyl groups in general versus t-butyl groups. (The 2,6-diisop ...
... ering the likely synthetic difficulties associated with R being a 2,6-di-tbutylphenyl group, we settled on the 2,6-diisopropylphenyl group, a choice that in part was in response to a comment by K. B. Sharpless concerning the value of isopropyl groups in general versus t-butyl groups. (The 2,6-diisop ...
Catalytic Asymmetric Induction. Highly Enantioselective Addition of
... with chiral modifiers.' In all cases, however, the procedures require stoichiometric or even excess amounts of the chiral sources.2 Accordingly, development of efficient chiral multiplication methods in the carbonyl alkylation constitutes a veritable challenge.' We here disclose a highly efficient a ...
... with chiral modifiers.' In all cases, however, the procedures require stoichiometric or even excess amounts of the chiral sources.2 Accordingly, development of efficient chiral multiplication methods in the carbonyl alkylation constitutes a veritable challenge.' We here disclose a highly efficient a ...
Enzymatic synthesis of bioactive compounds
... limiting factors for application are their acidicity and the rapid penetration into the deep epiderm, causing irritant effects at concentrations >10 %. To control their concentration and penetration to the skin’s intercellular spaces, AHAs have been grafted onto alkylglycosides, fatty acids, or fatt ...
... limiting factors for application are their acidicity and the rapid penetration into the deep epiderm, causing irritant effects at concentrations >10 %. To control their concentration and penetration to the skin’s intercellular spaces, AHAs have been grafted onto alkylglycosides, fatty acids, or fatt ...
DEPARTMENT OF CHEMISTRY
... Book: Physical Chemistry by P.W. Atkins; Physical Chemistry: Statistical mechanics by H. Metiu; Physical Chemistry: Chemical Kinetics by H. Metiu. CY49002 Advanced Physical Chemistry Laboratory (0-0-6: 4 credits) Prerequisite:Nil Charge transfer complex formation between anthracene and picric acid, ...
... Book: Physical Chemistry by P.W. Atkins; Physical Chemistry: Statistical mechanics by H. Metiu; Physical Chemistry: Chemical Kinetics by H. Metiu. CY49002 Advanced Physical Chemistry Laboratory (0-0-6: 4 credits) Prerequisite:Nil Charge transfer complex formation between anthracene and picric acid, ...
Separation of 2 (3), 9 (10), 16 (17), 23 (24)
... two shoulders. The problem was solved by designing new HPLC phases based on π-π interactions between the phthalocyanines and an aromatic part linked to silica gel to separate 2(3),9(10),16(17),23(24)-tetrasubstituted phthalocyanines. A monofunctionalized spacer, (4-aminobutyl)dimethylmethoxysilane ( ...
... two shoulders. The problem was solved by designing new HPLC phases based on π-π interactions between the phthalocyanines and an aromatic part linked to silica gel to separate 2(3),9(10),16(17),23(24)-tetrasubstituted phthalocyanines. A monofunctionalized spacer, (4-aminobutyl)dimethylmethoxysilane ( ...
PDF aldehydes and ketones
... If the carbonyl components are esters rather than ketones, stronger bases (e.g., sodium ethoxide) are required to generate the carbanions. This is known as Claisen condensation, and the product is a β-keto ester. ...
... If the carbonyl components are esters rather than ketones, stronger bases (e.g., sodium ethoxide) are required to generate the carbanions. This is known as Claisen condensation, and the product is a β-keto ester. ...
R - Evans - Harvard University
... The a-azido carboximide products have been shown to be versatile a-amino acid synthons that may be readily converted to n-amino acids as well as to N-protected a-amino acid derivatives. The racemization-free removal of the chiral auxiliary was achieved in high yield both by saponification and transe ...
... The a-azido carboximide products have been shown to be versatile a-amino acid synthons that may be readily converted to n-amino acids as well as to N-protected a-amino acid derivatives. The racemization-free removal of the chiral auxiliary was achieved in high yield both by saponification and transe ...
VITA - Trace: Tennessee Research and Creative Exchange
... Transition metal imide complexes have been prepared with mono-, bi-, and tridentate strong σ-donor ligands,10 yet no examples of strong σ-donor tetradentate ligands have been used to prepare metal imide complexes. This is particularly surprising given the tetradentate Ru-porphyrin complex has been t ...
... Transition metal imide complexes have been prepared with mono-, bi-, and tridentate strong σ-donor ligands,10 yet no examples of strong σ-donor tetradentate ligands have been used to prepare metal imide complexes. This is particularly surprising given the tetradentate Ru-porphyrin complex has been t ...
university of london thesis
... investigational work previously carried out into the Sn I like ring opening o f a model molecule, 1-methylcyclohexene oxide. This is followed by a description o f how a new methodology for the acidic ring opening o f epoxides was developed and optimised. This chemistry, leading to the formation o f ...
... investigational work previously carried out into the Sn I like ring opening o f a model molecule, 1-methylcyclohexene oxide. This is followed by a description o f how a new methodology for the acidic ring opening o f epoxides was developed and optimised. This chemistry, leading to the formation o f ...
Addition Reactions of Carbonyls Part 1
... Because electrophilic addition to a carbonyl group is reactantfavoured, whenever we see a gem-diol (two –OH groups on one carbon) or a carbon atom with a –OH group and a halogen attached, we expect it to collapse to a carbonyl group: H O C ...
... Because electrophilic addition to a carbonyl group is reactantfavoured, whenever we see a gem-diol (two –OH groups on one carbon) or a carbon atom with a –OH group and a halogen attached, we expect it to collapse to a carbonyl group: H O C ...
Discodermolide
(+)-Discodermolide is a polyketide natural product found to stabilize microtubule. (+)-discodermolide was isolated by Gunasekera and his co-workers at the Harbor Branch Oceanographic Institute from the deep-sea sponge Discodermia dissoluta in 1990. (+)-Discodermolide was found to be a potent inhibitor of tumor cell growth in several MDR cancer cell lines. (+)-discodermolide also shows some unique characters, including a linear backbone structure, immunosuppressive properties both in vitro and in vivo, potent induction of an accelerated senescence phenotype, and synergistic antiproliferative activity in combination with paclitaxel. Discodermolide was recognized as one of the most potent natural promoters of tubulin assembly. A large number of efforts toward the total synthesis of (+)-discodermolide were directed by its interesting biological activities and extreme scarcity of natural sources (0.002% w/w from frozen marine sponge). The compound supply necessary for complete clinical trials cannot be met by harvesting, isolation, and purification. As of 2005, attempts at synthesis or semi-synthesis by fermentation have proven unsuccessful. As a result, all discodermolide used in preclinical studies and clinical trials has come from large-scale total synthesis.