Bronsted acidic ionic liquid as an efficient and reusable catalyst for
... Various reaction parameters such as reaction time, temperature and IL concentration were studied using Bronsted acidic IL [NMP]+HSO4 as an optimized catalyst (Table 2). The results for the transesterification of MAA with 1-butanol demonstrate that chemical equilibrium is reached within 3 h at 80 °C ...
... Various reaction parameters such as reaction time, temperature and IL concentration were studied using Bronsted acidic IL [NMP]+HSO4 as an optimized catalyst (Table 2). The results for the transesterification of MAA with 1-butanol demonstrate that chemical equilibrium is reached within 3 h at 80 °C ...
Grignard Reagents
... to a starting compound using known and reliable reactions. “it is a problem solving technique for transforming the structure of a synthetic target molecule (TM) to a sequence of progressively simpler structures along the pathway which ultimately leads to simple or commercially available starting mat ...
... to a starting compound using known and reliable reactions. “it is a problem solving technique for transforming the structure of a synthetic target molecule (TM) to a sequence of progressively simpler structures along the pathway which ultimately leads to simple or commercially available starting mat ...
cycloadditions with singlet oxygen
... presumably stronger. The use of singlet oxygen is usually complicated by the competition between the ene reaction and the cycloadditions. The presence of allylic hydrogens next to a diene usually results in preferential formation of a hydroperoxide via an ene reaction instead of a [4+2] cycloadduct. ...
... presumably stronger. The use of singlet oxygen is usually complicated by the competition between the ene reaction and the cycloadditions. The presence of allylic hydrogens next to a diene usually results in preferential formation of a hydroperoxide via an ene reaction instead of a [4+2] cycloadduct. ...
Comprehensive Asymmetric Catalysis I-III Editors
... binds a ketone (lower π acidity) η1 (Fig. 7) [23, 24]. Because the former case results in increased electron density on the carbonyl due to a HOMO (metal)LUMO (carbonyl) interaction, this is less useful with respect to activation of α,β unsaturated carbonyls toward electron-rich dienes (normal elect ...
... binds a ketone (lower π acidity) η1 (Fig. 7) [23, 24]. Because the former case results in increased electron density on the carbonyl due to a HOMO (metal)LUMO (carbonyl) interaction, this is less useful with respect to activation of α,β unsaturated carbonyls toward electron-rich dienes (normal elect ...
Two-coordinate group 14 element(ii) hydrides as
... facile manner under ambient conditions. The rst hints that this might be possible came with the kinetic stabilisation of group 14 element(II) hydride complexes, a small number of which (e.g. I–V, Scheme 1)8–11 have been reported since the turn of the millennium.12 Of these, the three-coordinate sil ...
... facile manner under ambient conditions. The rst hints that this might be possible came with the kinetic stabilisation of group 14 element(II) hydride complexes, a small number of which (e.g. I–V, Scheme 1)8–11 have been reported since the turn of the millennium.12 Of these, the three-coordinate sil ...
CHEM1102 2014-J-8 June 2014 • Complete the following table
... • Methylphenidate, also known as Ritalin, is a psychostimulant drug approved for the treatment of attention-deficit disorder. Identify all stereogenic (chiral) centres in methylphenidate by clearly marking each with an asterisk (*) on the structure below. ...
... • Methylphenidate, also known as Ritalin, is a psychostimulant drug approved for the treatment of attention-deficit disorder. Identify all stereogenic (chiral) centres in methylphenidate by clearly marking each with an asterisk (*) on the structure below. ...
Synthesis of the hexoses
... opening of 2 produce two different diastereomers of 3. Not all errant hydroxide openings are a problem, however; for example the C-2 opening of 1 also gives 3. The modification of this process shown in equation 2 better suits the needs of a repeating cycle and is both selective and highly reliable. ...
... opening of 2 produce two different diastereomers of 3. Not all errant hydroxide openings are a problem, however; for example the C-2 opening of 1 also gives 3. The modification of this process shown in equation 2 better suits the needs of a repeating cycle and is both selective and highly reliable. ...
- Wiley Online Library
... very limited. We now report a method which makes it possible also to reduce amino acids, carboxylic acids, amides, nitriles, nitroalkenes, and sulfoxides with alkali metal borohydrides in good yields. We found that the addition of Me3SiC1 makes possible the reduction of a-amino acids with LiBH, in T ...
... very limited. We now report a method which makes it possible also to reduce amino acids, carboxylic acids, amides, nitriles, nitroalkenes, and sulfoxides with alkali metal borohydrides in good yields. We found that the addition of Me3SiC1 makes possible the reduction of a-amino acids with LiBH, in T ...
Document
... and HI. Chloroalkanes cannot be prepared by this method because Cl- is too poor a nucleophile. ...
... and HI. Chloroalkanes cannot be prepared by this method because Cl- is too poor a nucleophile. ...
ELECTROPHILIC ADDITIONS OF ALKENES AS THE
... by the action of an oxidizing agent, resulting in more oxidized forms of carbon, such as aldehydes, ketones, and carboxylic acids. All these reactions are covered in chapter 8 of the Wade text, 4th ed. The following is a summary of the most important representative types of these reactions. For full ...
... by the action of an oxidizing agent, resulting in more oxidized forms of carbon, such as aldehydes, ketones, and carboxylic acids. All these reactions are covered in chapter 8 of the Wade text, 4th ed. The following is a summary of the most important representative types of these reactions. For full ...
Pyrrolidine-2-carboxylic Acid (l
... Pyrrolidine-2-carboxylic acid commonly known as LProline (I) has shown, in recent times, excellent catalytic activity, in catalyzing a wide variety of reactions such as aldol,1,2 Mannich,3–5,10–12 Michael,6–9 in a highly enantioselective manner. These reactions have produced a variety of useful chir ...
... Pyrrolidine-2-carboxylic acid commonly known as LProline (I) has shown, in recent times, excellent catalytic activity, in catalyzing a wide variety of reactions such as aldol,1,2 Mannich,3–5,10–12 Michael,6–9 in a highly enantioselective manner. These reactions have produced a variety of useful chir ...
Recall
... Example: ROH can react with either acid or base. We want to temporarily Silyl ether. Does render the OH inert. not react with non Sequence of Steps: ...
... Example: ROH can react with either acid or base. We want to temporarily Silyl ether. Does render the OH inert. not react with non Sequence of Steps: ...
Elimination Reactions
... higher entropies than substitutions because eliminations have a greater number of products formed than that of starting compounds). • Any substitution that occurs must take place through an SN1 mechanism ...
... higher entropies than substitutions because eliminations have a greater number of products formed than that of starting compounds). • Any substitution that occurs must take place through an SN1 mechanism ...
Arginine- or Lysine-catalyzed Michael Addition of Nitromethane to α
... addition of nitroalkanes provide a variety of key building blocks for various compounds, such as an amine, ketone, alkane, and alkene.4 The most widely studied amino acid as a catalyst is proline. The reaction mechanisms of the proline-catalyzed reactions with carbonyl compounds are mainly involved ...
... addition of nitroalkanes provide a variety of key building blocks for various compounds, such as an amine, ketone, alkane, and alkene.4 The most widely studied amino acid as a catalyst is proline. The reaction mechanisms of the proline-catalyzed reactions with carbonyl compounds are mainly involved ...
Unsaturated Hydrocarbons I : Alkenes
... Alkenes that contain two double bonds are called Dienes: If the double bonds are separated by only one single bond, the diene is said to be conjugated. If the double bonds are separated by more than one single bond, the diene is called non conjugated diene. Dienes are named by the IUPAC system ...
... Alkenes that contain two double bonds are called Dienes: If the double bonds are separated by only one single bond, the diene is said to be conjugated. If the double bonds are separated by more than one single bond, the diene is called non conjugated diene. Dienes are named by the IUPAC system ...
... environmental and cheaper tools to improve a wide range of processes, which will reduce energy and raw material consumption, and to generate less wastes and toxic side-products. The principal drawbacks hindering a broader applicability of enzymes are the high production cost and the low yields [1]. ...
Document
... Typical of chain reactions in low-molecular weight species. The carbon-carbon double band is, because of its relatively low stability, particularly susceptible to attach by a free radical. The reaction of the double band with a radical proceeds Well for compounds of the type CH2=CHX and CH2=CXY call ...
... Typical of chain reactions in low-molecular weight species. The carbon-carbon double band is, because of its relatively low stability, particularly susceptible to attach by a free radical. The reaction of the double band with a radical proceeds Well for compounds of the type CH2=CHX and CH2=CXY call ...
Electophilic Aromatic Substituion
... Ketone is converted into an alkylbenzene by catalytic hydrogenation over Pd catalyst ...
... Ketone is converted into an alkylbenzene by catalytic hydrogenation over Pd catalyst ...
Electophilic Aromatic Substituion
... Ketone is converted into an alkylbenzene by catalytic hydrogenation over Pd catalyst ...
... Ketone is converted into an alkylbenzene by catalytic hydrogenation over Pd catalyst ...
Sodium Borohydride Reduction of Vanillin
... When lithium aluminum hydride (LiAlH4) was introduced as a reducing agent in the late 1940s, it brought about a revolution in the preparation of alcohols by reduction. At that time, the most popular reducing agents for carbonyl compounds were sodium metal and gaseous hydrogen under pressure. The gre ...
... When lithium aluminum hydride (LiAlH4) was introduced as a reducing agent in the late 1940s, it brought about a revolution in the preparation of alcohols by reduction. At that time, the most popular reducing agents for carbonyl compounds were sodium metal and gaseous hydrogen under pressure. The gre ...
Student Worksheet Part 1 Synthesis w/ answers
... 3. The reaction can only happen at higher temperatures, which ties in with (2) and means that removing sample from the reaction vessel essentially quenches (stops) the reaction as soon as it cools below 200°C. 4. Because the reaction is relatively slow, thermodynamic considerations are important, me ...
... 3. The reaction can only happen at higher temperatures, which ties in with (2) and means that removing sample from the reaction vessel essentially quenches (stops) the reaction as soon as it cools below 200°C. 4. Because the reaction is relatively slow, thermodynamic considerations are important, me ...
NUCLEOPHILIC SUBSTITUTION & ELIMINATION ON Csp 3
... - The substrate: 1o C (or, not so good, 2º C) - The nucleophile: good - The leaving group: low pKa of conjugate acid - The solvent: polar, aprotic (next slides) The reaction flow & the transition state: ...
... - The substrate: 1o C (or, not so good, 2º C) - The nucleophile: good - The leaving group: low pKa of conjugate acid - The solvent: polar, aprotic (next slides) The reaction flow & the transition state: ...
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.