Alcohols, Phenols and Ethers
... The reaction with R’COOH and (R’ CO)2O is reversible, so cone, H2SO4 is used to remove water. The reaction with R’ COCI is carried out in the presence of pyridine so as to neutralise HCI which is formed during the reaction. The introduction of acetyl (CH3CO-) group in phenols is known as acetylation ...
... The reaction with R’COOH and (R’ CO)2O is reversible, so cone, H2SO4 is used to remove water. The reaction with R’ COCI is carried out in the presence of pyridine so as to neutralise HCI which is formed during the reaction. The introduction of acetyl (CH3CO-) group in phenols is known as acetylation ...
communication - Kyushu University Library
... cyclohexanones and cycloheptanones having simple alkyl groups were efficiently transformed into the corresponding 2-substituted cyclic ketones in excellent yields and high enantioselectivities (Table 2). When comparing the 10 and 2 mol% conditions for 3 substrates, the former condition gave slightly ...
... cyclohexanones and cycloheptanones having simple alkyl groups were efficiently transformed into the corresponding 2-substituted cyclic ketones in excellent yields and high enantioselectivities (Table 2). When comparing the 10 and 2 mol% conditions for 3 substrates, the former condition gave slightly ...
Novel Brønsted-acidic ionic liquids based on benzothiazolium
... polystyrene (PS)-supported ionic liquid catalysts can be recycled easily by filtration, they cannot serve as homogeneous catalysts to promote reactions.14 Davis15 and Wang et al.16,17 investigated Brønsted acidic ILs in some esterification reactions and removed the ILs by simple filtration after the ...
... polystyrene (PS)-supported ionic liquid catalysts can be recycled easily by filtration, they cannot serve as homogeneous catalysts to promote reactions.14 Davis15 and Wang et al.16,17 investigated Brønsted acidic ILs in some esterification reactions and removed the ILs by simple filtration after the ...
cleavage of methyl ethers with iodotrimethylsilane
... 5. The product is sometimes contaminated with a small amount of hexamethyldisiloxane. The amount of this contaminant is minimized by using longer reaction times and by careful handling to avoid contact with atmospheric moisture. The product may become discolored during storage, in which case it may ...
... 5. The product is sometimes contaminated with a small amount of hexamethyldisiloxane. The amount of this contaminant is minimized by using longer reaction times and by careful handling to avoid contact with atmospheric moisture. The product may become discolored during storage, in which case it may ...
Organometallic Chemistry
... reaction for C-C bond formation, it is often accompanied by competing side reactions such as enolization, reduction, or aldol condensation of the carbonyl substrate. • Organomagnesium compounds can act not only as nucleophiles, but also as bases • It can convert ketones with enolizable hydrogens to ...
... reaction for C-C bond formation, it is often accompanied by competing side reactions such as enolization, reduction, or aldol condensation of the carbonyl substrate. • Organomagnesium compounds can act not only as nucleophiles, but also as bases • It can convert ketones with enolizable hydrogens to ...
Chapter 4 Functional Group Transformations: Oxidation and
... Review - Pagliaro et. al. Chem. Soc. Rev. 2005, 34, 837-845 ...
... Review - Pagliaro et. al. Chem. Soc. Rev. 2005, 34, 837-845 ...
Chem 150 Unit 9 - Biological Molecules II
... The same reaction can also be used to reduce aldehydes and ketones to alcohols: ...
... The same reaction can also be used to reduce aldehydes and ketones to alcohols: ...
Chem 2423-Test 2 - HCC Learning Web
... 17. The transition state is found at point _____ on the diagram. 18. The products are found at point _____ on the diagram. 19. The free-energy change for the reaction is indicated at point _____ on the diagram. 20. The reactants are found at point _____ on the diagram. ...
... 17. The transition state is found at point _____ on the diagram. 18. The products are found at point _____ on the diagram. 19. The free-energy change for the reaction is indicated at point _____ on the diagram. 20. The reactants are found at point _____ on the diagram. ...
Hydrogen bonding
... • Yeast is killed by ethanol concentrations in excess of about 15%, and that limits the purity of the ethanol that can be produced. The ethanol is separated from the mixture by fractional distillation to give 96% pure ethanol. • For theoretical reasons, it is impossible to remove the last 4% of wate ...
... • Yeast is killed by ethanol concentrations in excess of about 15%, and that limits the purity of the ethanol that can be produced. The ethanol is separated from the mixture by fractional distillation to give 96% pure ethanol. • For theoretical reasons, it is impossible to remove the last 4% of wate ...
Applications of Phosphorus, Sulfur, Silicon and Boron Chemistry:
... preferentially to the least hindered carbon of the C=C bond. However there is also an “electronic factor”, which may be significant when the alkene has an electron withdrawing or donating group directly attached. If an alkyl borane is used, especially hindered ones, then the regioselectivity is ofte ...
... preferentially to the least hindered carbon of the C=C bond. However there is also an “electronic factor”, which may be significant when the alkene has an electron withdrawing or donating group directly attached. If an alkyl borane is used, especially hindered ones, then the regioselectivity is ofte ...
Asymmetric Glycine Enolate Aldol Reactions
... In a typical procedure, 1.2 equiv of stannous triflate in anhydrous tetrahydrofuran (THF) is cooled to -78 "C and 1.5 equiv of N-ethylpiperidine is added, followed by a precooled solution of 3c in THF. After the reaction mixture is stirred for 1.5 h, the aldehyde is added and stirring is continued a ...
... In a typical procedure, 1.2 equiv of stannous triflate in anhydrous tetrahydrofuran (THF) is cooled to -78 "C and 1.5 equiv of N-ethylpiperidine is added, followed by a precooled solution of 3c in THF. After the reaction mixture is stirred for 1.5 h, the aldehyde is added and stirring is continued a ...
Catalytic Nucleophilic Fluorination of Secondary and Tertiary
... catalyzed the formation of propargylic fluoride 2 a in good yield from propargylic tosylate 1 a-OTs in the presence of Et3N·3 HF as the fluoride source at 30 8C,[27] with the formation of only a trace amount of enyne 3 (Table 1, entry 1). To our knowledge, Cu(NHC) complexes have not previously been ...
... catalyzed the formation of propargylic fluoride 2 a in good yield from propargylic tosylate 1 a-OTs in the presence of Et3N·3 HF as the fluoride source at 30 8C,[27] with the formation of only a trace amount of enyne 3 (Table 1, entry 1). To our knowledge, Cu(NHC) complexes have not previously been ...
10. Alkyl Halides
... This reaction does not stop at the monochlorination stage but may continue to give dichloro, trichloro and even tetrachloro products. Furthermore alkanes having more than one kind of hydrogen give more than one kind of monochlorination product in addition to the ...
... This reaction does not stop at the monochlorination stage but may continue to give dichloro, trichloro and even tetrachloro products. Furthermore alkanes having more than one kind of hydrogen give more than one kind of monochlorination product in addition to the ...
jDonvert the following Fischer projections to dimensional formulas
... determining step for both Bromine and Chlorine. (Be sure to show the relative energies of activation and whether the reactions are exothermic or endothermic). (b) Draw and show the difference in the transition states for Bromine and Chlorine in the rate determining step of these reactions. (c) Using ...
... determining step for both Bromine and Chlorine. (Be sure to show the relative energies of activation and whether the reactions are exothermic or endothermic). (b) Draw and show the difference in the transition states for Bromine and Chlorine in the rate determining step of these reactions. (c) Using ...
Alcohols
... Can be more or less acidic than phenol itself. Remember, the acidity of any alcohol is determined by the stability of the alkoxide or phenoxide anion produced. The more stable the anion produced the more acidic the alcohol An electron-withdrawing substituent makes a phenol more acidic by delocalizin ...
... Can be more or less acidic than phenol itself. Remember, the acidity of any alcohol is determined by the stability of the alkoxide or phenoxide anion produced. The more stable the anion produced the more acidic the alcohol An electron-withdrawing substituent makes a phenol more acidic by delocalizin ...
New L-Serine Derivative Ligands as Cocatalysts for Diels
... totally suppressed. This suggests that the cation coordinates to the basic amine group of 6 and the resulting complex is not sufficiently acidic to catalyze the Diels-Alder reaction. The Boc-protection of serine 8 led to serine ligand 4. The addition of 4 to a suspension of Cu(OTf)2 in dichlorometha ...
... totally suppressed. This suggests that the cation coordinates to the basic amine group of 6 and the resulting complex is not sufficiently acidic to catalyze the Diels-Alder reaction. The Boc-protection of serine 8 led to serine ligand 4. The addition of 4 to a suspension of Cu(OTf)2 in dichlorometha ...
Boron Reagents in Process Chemistry: Excellent
... intermediate in reactivity.The amine and sulfide borane complexes offer concentration advantages over BTHF. For example, dimethyl sulfide borane (DMSB) is 10 times more concentrated than BTHF. Both amine and sulfide borane complexes are more stable than BTHF at ambient or higher temperatures. The av ...
... intermediate in reactivity.The amine and sulfide borane complexes offer concentration advantages over BTHF. For example, dimethyl sulfide borane (DMSB) is 10 times more concentrated than BTHF. Both amine and sulfide borane complexes are more stable than BTHF at ambient or higher temperatures. The av ...
8. Alkynes: An Introduction to Organic Synthesis
... Addition of Bromine and Chlorine Initial addition usually gives trans intermediate Can often be stopped at this stage if desired ...
... Addition of Bromine and Chlorine Initial addition usually gives trans intermediate Can often be stopped at this stage if desired ...
1,1,1,5,5,5-hexafluoroacetylacetonato
... region gave three prominent absorption bands at 287, 374 and 525 nm. The band at 287 nm has a molar absorptivity coefficient of 13000 L/mol cm. The band at 374 nm and 525 nm have molar absorptivity coefficient of 7667 and 3889 L/mol cm respectively. This band at 287 nm is found in all β-diketones an ...
... region gave three prominent absorption bands at 287, 374 and 525 nm. The band at 287 nm has a molar absorptivity coefficient of 13000 L/mol cm. The band at 374 nm and 525 nm have molar absorptivity coefficient of 7667 and 3889 L/mol cm respectively. This band at 287 nm is found in all β-diketones an ...
STUDY OF CHIRAL AZA-MACROCYCLIC LIGANDS INVOLVED IN
... Cu+ and Cu2+ complexes with 11 ligand. They show strong catalytic effect during the ascorbic acid oxidation, in aerobic conditions. While, as mentioned above, molecular recognition using non-natural receptors of metal cations has reached a high level of maturity and sophistication, and as a conseque ...
... Cu+ and Cu2+ complexes with 11 ligand. They show strong catalytic effect during the ascorbic acid oxidation, in aerobic conditions. While, as mentioned above, molecular recognition using non-natural receptors of metal cations has reached a high level of maturity and sophistication, and as a conseque ...
Organocatalysed asymmetric Mannich reactions
... the aforementioned groups. Various aliphatic aldehydes were used as Mannich donors 16 and generally good results were obtained. However it was observed that employment of acetaldehyde and 2-substituted acetaldehydes did not result in the expected products. The acceptor aldehyde 21 scope was also exp ...
... the aforementioned groups. Various aliphatic aldehydes were used as Mannich donors 16 and generally good results were obtained. However it was observed that employment of acetaldehyde and 2-substituted acetaldehydes did not result in the expected products. The acceptor aldehyde 21 scope was also exp ...
17: Oxidation and Reduction
... We can prevent this by using modified Cr(VI) reagents that we describe later in this section. We can also distill the intermediate aldehyde from the reaction mixture as it forms before it is oxidized further. This is often possible because boiling points of aldehydes are usually much lower than thos ...
... We can prevent this by using modified Cr(VI) reagents that we describe later in this section. We can also distill the intermediate aldehyde from the reaction mixture as it forms before it is oxidized further. This is often possible because boiling points of aldehydes are usually much lower than thos ...
Microsoft Word
... (particularly Pd on activated carbon) is commonly used in the low pressure hydrogenation of nitro groups in aromatic compounds A few studies have been reported on the hydrogenation of o-nitrophenol on, palladium catalyst. However, no detailed investigation covering the effect of reaction medium (or ...
... (particularly Pd on activated carbon) is commonly used in the low pressure hydrogenation of nitro groups in aromatic compounds A few studies have been reported on the hydrogenation of o-nitrophenol on, palladium catalyst. However, no detailed investigation covering the effect of reaction medium (or ...
Wolff–Kishner reduction
The Wolff–Kishner reduction is a reaction used in organic chemistry to convert carbonyl functionalities into methylene groups. In the context of complex molecule synthesis, it is most frequently employed to remove a carbonyl group after it has served its synthetic purpose of activating an intermediate in a preceding step. As such, there is no obvious retron for this reaction. Originally reported by Nikolai Kischner in 1911 and Ludwig Wolff in 1912, it has been applied to the total synthesis of scopadulcic acid B, aspidospermidine and dysidiolide.In general, the reaction mechanism first involves the in situ generation of a hydrazone by condensation of hydrazine with the ketone or aldehyde substrate. Sometimes it is however advantageous to use a pre-formed hydrazone as substrate (see modifications). The hydrazone is deprotonated by alkoxide base followed by a concerted, rate-determining step in which a diimide anion is formed. Collapse of this alkyldiimde with loss of N2 leads to formation of an alkylanion which can be protonated by solvent to give the desired product.Because the Wolff–Kishner reduction requires highly basic conditions, it is unsuitable for base-sensitive substrates. However, this method can be superior over the related Clemmensen reduction for acid-sensitive compounds such as pyrroles and for high-molecular weight compounds.