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In its simplest implementation, base induces conversion of an aldehyde or a ketone to the aldol product. One example involves the aldol condensation of propionaldehyde: 2 CH 3 CH 2 CHO → CH 3 CH 2 CH(OH)CH(CH 3)CHO. Featuring the RCH(OH)CHR'C(O)R" grouping, the product is an aldol. In this case . Such reactions are called aldol aldol ...
It can also be prepared by combining ethylene, CO, and H 2. [4] When the reaction is catalyzed by dicobalt octacarbonyl, water can be used as a source of hydrogen.A proposed intermediate is the ethylene-propionyl species [CH 3 C(O)Co(CO) 3 (ethylene)] which undergoes a migratory insertion to form [CH 3 COCH 2 CH 2 Co(CO) 3].
Levi and Zanetti extended the Knorr synthesis in 1894 to the use of acetylacetone (2,4-pentanedione) in reaction with ethyl 2-oximinoacetoacetate. The result was ethyl 4-acetyl-3,5-dimethylpyrrole-2-carboxylate, where "OEt" = R 1 = R 3 = Me, and R 2 = COOEt. [9] The 4-acetyl group could easily be converted to a 4-ethyl group by Wolff-Kishner ...
The mechanism for base-catalyzed aldol condensation can be seen in the image below. A mechanism for aldol condensation in basic conditions, which occurs via enolate intermediates and E1CB elimination. The process begins when a free hydroxide (strong base) strips the highly acidic proton at the alpha carbon of the aldehyde.
The Hajos–Parrish–Eder–Sauer–Wiechert and Barbas-List [1] reactions in organic chemistry are a family of proline-catalysed asymmetric aldol reactions.. In the 1970s, two research groups discovered (and published) almost simultaneously their discoveries of two related intramolecular reactions: Zoltan Hajos and David Parrish at Hoffmann-La Roche [2] [3] and Rudolf Wiechert et al at ...
2,4-Dimethylpentane is an alkane with the chemical formula [(H 3 C) 2 CH] 2 CH 2. This colorless hydrocarbon is produced in large quantities in oil refineries. It results from the alkylation of isobutane by propylene. [1] Often referred to as "alkylate", it is blended with other gasoline components to give a high octane fuel.
This page contains tables of azeotrope data for various binary and ternary mixtures of solvents. The data include the composition of a mixture by weight (in binary azeotropes, when only one fraction is given, it is the fraction of the second component), the boiling point (b.p.) of a component, the boiling point of a mixture, and the specific gravity of the mixture.
In organic chemistry, the Mannich reaction is a three-component organic reaction that involves the amino alkylation of an acidic proton next to a carbonyl (C=O) functional group by formaldehyde (H−CHO) and a primary or secondary amine (−NH 2) or ammonia (NH 3). [1] The final product is a β-amino-carbonyl compound also known as a Mannich base.