AddCorrections(KKH) - Spiral
... Traditionally, there are three general ways of converting alkenes into alcohols. The first route requires protonation of the C=C bond to form a carbocation intermediate, which is then attacked by water to give an alcohol (Scheme 1, eq. 1). Selective formation of the thermodynamically-preferred carbo ...
... Traditionally, there are three general ways of converting alkenes into alcohols. The first route requires protonation of the C=C bond to form a carbocation intermediate, which is then attacked by water to give an alcohol (Scheme 1, eq. 1). Selective formation of the thermodynamically-preferred carbo ...
Solid-Phase Organic Synthesis: Creation of Carbon
... Four sets of solid-phase reactions are described in Table I. The resin-bound substrate for the first set was obtained by acylation of H-Nph-PAL-resin with succinic anhydride–DIEA (5 equivalents each) in CH2Cl2, 2 h, 25 °C, to reach a ninhydrin-negative support, then adding aminoacetaldehyde dimethyl ...
... Four sets of solid-phase reactions are described in Table I. The resin-bound substrate for the first set was obtained by acylation of H-Nph-PAL-resin with succinic anhydride–DIEA (5 equivalents each) in CH2Cl2, 2 h, 25 °C, to reach a ninhydrin-negative support, then adding aminoacetaldehyde dimethyl ...
Alcohols General formula R-OH hydroxyl group Nomenclature
... CH3CH2CH2CH2Cl 80oC Using PBr3 there is no carbocation formed and so we do not get rearrangements and this is usually the preferred reagent for converting alcohols to alkyl bromides. CH3CH2CH2CH2OH ...
... CH3CH2CH2CH2Cl 80oC Using PBr3 there is no carbocation formed and so we do not get rearrangements and this is usually the preferred reagent for converting alcohols to alkyl bromides. CH3CH2CH2CH2OH ...
Common aldehydes and ketones
... • A compound containing a carbonyl group (C=O) is normally in rapid equilibrium with an enol tautomer, which contains a pair of doubly bonded carbon atoms adjacent to a hydroxyl (−OH) group, C=C-OH. The keto form predominates at equilibrium for most ketones. Nonetheless, the enol form is important f ...
... • A compound containing a carbonyl group (C=O) is normally in rapid equilibrium with an enol tautomer, which contains a pair of doubly bonded carbon atoms adjacent to a hydroxyl (−OH) group, C=C-OH. The keto form predominates at equilibrium for most ketones. Nonetheless, the enol form is important f ...
Factors influencing ring closure through olefin metathesis – A
... or radical species. Common rings such as 5–7 membered ones are easily available by these methods. However, formation of medium or large rings by these methods either proceeds with low yields or does not proceed at all due to unfavourable enthalpic and entropic factors. In recent years, olefin metath ...
... or radical species. Common rings such as 5–7 membered ones are easily available by these methods. However, formation of medium or large rings by these methods either proceeds with low yields or does not proceed at all due to unfavourable enthalpic and entropic factors. In recent years, olefin metath ...
Reaction of orthoesters with alcohols in the presence of acidic
... as stated before, this reaction is found to be general with regard to various orthoesters but selective with respect to various primary allylic and benzylic alcohols. However, when SiO2 is used as the catalyst, we could isolate corresponding O-acetylated compound 3 as major product (in case of prima ...
... as stated before, this reaction is found to be general with regard to various orthoesters but selective with respect to various primary allylic and benzylic alcohols. However, when SiO2 is used as the catalyst, we could isolate corresponding O-acetylated compound 3 as major product (in case of prima ...
Unit 4 Chemical Kinetics and Chemical Equilibrium
... NaI (E2 mechanism) Zn/HOAc (redox reaction) ...
... NaI (E2 mechanism) Zn/HOAc (redox reaction) ...
Oxidation Reactions
... be oxidised selectively. 2. Chemoselectivity - oxidation of primary alcohols requires control as there are two potential products: the carboxylic acid or the aldehyde. Aldehydes are extremely important in organic synthesis; thus controlled oxidation from an alcohol to an aldehyde, avoiding over-oxid ...
... be oxidised selectively. 2. Chemoselectivity - oxidation of primary alcohols requires control as there are two potential products: the carboxylic acid or the aldehyde. Aldehydes are extremely important in organic synthesis; thus controlled oxidation from an alcohol to an aldehyde, avoiding over-oxid ...
stereochemistry of internucleotide bond formation by the h
... stereoselectivity during condensing agents-promoted formation of an internucleotidic bond1,2. The activation of ribonucleoside H-phosphonates of type 1 with pivaloyl chloride yields two diastereomers (A and B, Fig. 1) of mixed anhydrides 2. These isomers have to exist in a rapid equilibrium to regen ...
... stereoselectivity during condensing agents-promoted formation of an internucleotidic bond1,2. The activation of ribonucleoside H-phosphonates of type 1 with pivaloyl chloride yields two diastereomers (A and B, Fig. 1) of mixed anhydrides 2. These isomers have to exist in a rapid equilibrium to regen ...
Chapter 9
... Fluorine is too reactive to give mono-fluorinated products For Iodine, an oxidizing agent such as hydrogen peroxide or a copper salt such as CuCl2 must be added to the reaction • These substances oxidize I2 to the electrophilic species that reacts as if it were I+ • The aromatic ring reacts with the ...
... Fluorine is too reactive to give mono-fluorinated products For Iodine, an oxidizing agent such as hydrogen peroxide or a copper salt such as CuCl2 must be added to the reaction • These substances oxidize I2 to the electrophilic species that reacts as if it were I+ • The aromatic ring reacts with the ...
Montmorillonite: An efficient, heterogeneous and
... • May lower the activation energy of a reaction by stabilizing the transition state • May act as a general acid or base • Environmentally benign • Use of clays as catalysts allows for them to be recycled, which further increases their economic efficiency. • Furthermore, reactions that are catalyzed ...
... • May lower the activation energy of a reaction by stabilizing the transition state • May act as a general acid or base • Environmentally benign • Use of clays as catalysts allows for them to be recycled, which further increases their economic efficiency. • Furthermore, reactions that are catalyzed ...
ENZYME MIMIC ASYMMETRIC ALDOL REACTIONS
... residue and concomitantly activate the aldehyde acceptor with an active site acidic residue. It would be promising if the catalyst simultaneously activates both the ketone donor and aldehyde acceptor. Amino acids could be potential catalysts since they can form enamines with the amino group and acti ...
... residue and concomitantly activate the aldehyde acceptor with an active site acidic residue. It would be promising if the catalyst simultaneously activates both the ketone donor and aldehyde acceptor. Amino acids could be potential catalysts since they can form enamines with the amino group and acti ...
14. The Direct and Enantioselective Organocatalytic -Oxidation of Aldehydes
... Yamamoto and co-workers recently disclosed a conceptually novel approach to the enantioselective oxidation of tin enolates using nitrosobenzene4 as an electrophilic source of oxygen in the presence of various BINAP-AgX catalysts.5 On the basis of these studies, as well as the recent elegant work by ...
... Yamamoto and co-workers recently disclosed a conceptually novel approach to the enantioselective oxidation of tin enolates using nitrosobenzene4 as an electrophilic source of oxygen in the presence of various BINAP-AgX catalysts.5 On the basis of these studies, as well as the recent elegant work by ...
Ch 10- Alcohols and Ethers
... epoxide must be syn-addition • With straight chain alkenes, the reaction is stereospecific as well • The resulting oxirane will have the same configuration as the alkene had! • Examples: ...
... epoxide must be syn-addition • With straight chain alkenes, the reaction is stereospecific as well • The resulting oxirane will have the same configuration as the alkene had! • Examples: ...
![Synthesis of [RuCl2(NO)2(THF)] and its Double CN BondForming](http://s1.studyres.com/store/data/001773792_1-763ad0089529123821e01ed17077bbf2-300x300.png)
Synthesis of [RuCl2(NO)2(THF)] and its Double CN BondForming
... investigation, methods for controlling the reactivity of nitric oxide at transition-metal centers have received considerably less attention.[1–3] For example, the migratory insertion of NO into metal–alkyl or metal–aryl bonds has been observed in only a handful of metal complexes,[3] despite the ana ...
... investigation, methods for controlling the reactivity of nitric oxide at transition-metal centers have received considerably less attention.[1–3] For example, the migratory insertion of NO into metal–alkyl or metal–aryl bonds has been observed in only a handful of metal complexes,[3] despite the ana ...
Direct organocatalytic enantioselective a-aminomethylation
... complexes.10 Recently, Shibasaki and Matsunaga,11 and Trost and co-workers12 developed di-nuclear zinc organometallic complexes as catalyst for the direct catalytic enantioselective Mannich-type reactions between hydroxyarylketones and preformed imines. In addition, Jørgensen and co-workers have dev ...
... complexes.10 Recently, Shibasaki and Matsunaga,11 and Trost and co-workers12 developed di-nuclear zinc organometallic complexes as catalyst for the direct catalytic enantioselective Mannich-type reactions between hydroxyarylketones and preformed imines. In addition, Jørgensen and co-workers have dev ...
Iron(II) Chloride–1,1′-Binaphthyl-2,2′-diamine
... trapping agent, to the reaction mixture. These results indicate that a radical intermediate is most likely involved in the initial steps of the domino transformation. This explains the observed fact that aliphatic alcohols are more reactive than benzyl alcohol, since benzylic radicals are stabilized ...
... trapping agent, to the reaction mixture. These results indicate that a radical intermediate is most likely involved in the initial steps of the domino transformation. This explains the observed fact that aliphatic alcohols are more reactive than benzyl alcohol, since benzylic radicals are stabilized ...
Asymmetric Catalytic Aldol
... • Aldolases are a specific group of lysases that catalyse the stereoselective addition of a ketone donor to an aldehyde acceptor. • Over 30 have been identified to date • Type I aldolases are primarily found in animals and plants and activate the donor by forming a schiff base as an intermediate. • ...
... • Aldolases are a specific group of lysases that catalyse the stereoselective addition of a ketone donor to an aldehyde acceptor. • Over 30 have been identified to date • Type I aldolases are primarily found in animals and plants and activate the donor by forming a schiff base as an intermediate. • ...
Novel Brønsted-acidic ionic liquids based on benzothiazolium
... All chemicals (AR) were commercially available and used without further purification. The melting points were determined on an XRC-1 melting point apparatus (Sichuan University Instrument Factory, P. R. China). The 1H- and 13C-nuclear magnetic resonance (NMR) spectra were recorded on an AV-400 spect ...
... All chemicals (AR) were commercially available and used without further purification. The melting points were determined on an XRC-1 melting point apparatus (Sichuan University Instrument Factory, P. R. China). The 1H- and 13C-nuclear magnetic resonance (NMR) spectra were recorded on an AV-400 spect ...
a,b
... • Best reactions are derived from addition of a b-keto ester or other 1,3-dicarbonyl compound to an unhindered a,bunsaturated ketone • Ethyl acetoacetate reacts with but-3-en-2-one in the presence of sodium ethoxide to yield the Michael addition product ...
... • Best reactions are derived from addition of a b-keto ester or other 1,3-dicarbonyl compound to an unhindered a,bunsaturated ketone • Ethyl acetoacetate reacts with but-3-en-2-one in the presence of sodium ethoxide to yield the Michael addition product ...
Organocatalysed asymmetric Mannich reactions
... with a dr ranging from 1 : 1 to 4 : 1 (syn : anti). The analogous proline-catalysed addition of protected glycolaldehydes 29 to aromatic imines 30 afforded b-aminoa-oxyaldehydes 25 in good yields (up to 95%) and high enantioselectivity (up to 99% ee). The diastereoselectivity was generally moderate ...
... with a dr ranging from 1 : 1 to 4 : 1 (syn : anti). The analogous proline-catalysed addition of protected glycolaldehydes 29 to aromatic imines 30 afforded b-aminoa-oxyaldehydes 25 in good yields (up to 95%) and high enantioselectivity (up to 99% ee). The diastereoselectivity was generally moderate ...
Chapter 1 Organoaluminum Reagents for Selective Organic
... Claisen rearrangement is accelerated significantly by bulky aluminum reagents [151, 167]. With MABR, the rearrangement of 1-substituted-2-propenyl vinyl ether derivatives takes place in a few seconds even at -78 °C to give the 4-(Z)-alkenols after reduction with NaBH4. When MABR is replaced by MAPH, ...
... Claisen rearrangement is accelerated significantly by bulky aluminum reagents [151, 167]. With MABR, the rearrangement of 1-substituted-2-propenyl vinyl ether derivatives takes place in a few seconds even at -78 °C to give the 4-(Z)-alkenols after reduction with NaBH4. When MABR is replaced by MAPH, ...
Organic Synthesis - National Open University of Nigeria
... Oxidation of ketones On oxidation with peroxy-acids, ketones are converted into esters or lactones. This reaction was discovered in 1899 by Baeyer and Villiger. Better yields are obtained with organic peroxy-acids such as perbenzoic acid, peracetic acid and trifluoroperacetic acid; although in pract ...
... Oxidation of ketones On oxidation with peroxy-acids, ketones are converted into esters or lactones. This reaction was discovered in 1899 by Baeyer and Villiger. Better yields are obtained with organic peroxy-acids such as perbenzoic acid, peracetic acid and trifluoroperacetic acid; although in pract ...
Chapter 11 - Alcohols and Ethers1
... retention of con guration in the formation of a sulfonate ester because the C−O bond is not ...
... retention of con guration in the formation of a sulfonate ester because the C−O bond is not ...
Nonracemic Allylic Boronates through Enantiotopic-Group
... allylic boronates are attractive reagents: not only can they be directly converted to chiral γ,γ-disubstituted allylic alcohols and amines by oxidation and amination, but they can also engage in carbonyl allylations that establish chiral all-carbon quaternary centers.1 However, in spite of their abi ...
... allylic boronates are attractive reagents: not only can they be directly converted to chiral γ,γ-disubstituted allylic alcohols and amines by oxidation and amination, but they can also engage in carbonyl allylations that establish chiral all-carbon quaternary centers.1 However, in spite of their abi ...
Diels–Alder reaction
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The Diels–Alder reaction is an organic chemical reaction (specifically, a [4+2] cycloaddition) between a conjugated diene and a substituted alkene, commonly termed the dienophile, to form a substituted cyclohexene system. It was first described by Otto Paul Hermann Diels and Kurt Alder in 1928, for which work they were awarded the Nobel Prize in Chemistry in 1950. The Diels–Alder reaction is particularly useful in synthetic organic chemistry as a reliable method for forming 6-membered systems with good control over regio- and stereochemical properties. The underlying concept has also been applied to other π-systems, such as carbonyls and imines, to furnish the corresponding heterocycles, known as the hetero-Diels–Alder reaction. Diels–Alder reactions can be reversible under certain conditions; the reverse reaction is known as the retro-Diels–Alder reaction.