Search results
Results from the WOW.Com Content Network
Ethyl diazoacetate (N=N=CHC(O)OC 2 H 5) is a diazo compound and a reagent in organic chemistry. It was discovered by Theodor Curtius in 1883. [4] The compound can be prepared by reaction of the ethyl ester of glycine with sodium nitrite and sodium acetate in water. As a carbene precursor, it is used in the cyclopropanation of alkenes.
The Buchner ring expansion is a two-step organic C-C bond forming reaction used to access 7-membered rings. The first step involves formation of a carbene from ethyl diazoacetate, which cyclopropanates an aromatic ring. The ring expansion occurs in the second step, with an electrocyclic reaction opening the cyclopropane ring to form the 7 ...
In organic chemistry, the Roskamp reaction is a name reaction describing the reaction between α-diazoesters (such as ethyl diazoacetate) and aldehydes to form β-ketoesters, often utilizing various Lewis acids (such as BF 3, SnCl 2, and GeCl 2) as catalysts. [1] [2] [3] The reaction is notable for its mild reaction conditions and selectivity.
The Buchner–Curtius–Schlotterbeck reaction is the reaction of aldehydes or ketones with aliphatic diazoalkanes to form homologated ketones. [1] It was first described by Eduard Buchner and Theodor Curtius in 1885 [ 2 ] and later by Fritz Schlotterbeck in 1907. [ 3 ]
This reaction is also called the Regitz diazo transfer. [7] Examples are the synthesis of tert-butyl diazoacetate [8] and diazomalonate. [9] Methyl phenyldiazoacetate is generated in this way by treating methyl phenylacetate with p-acetamidobenzenesulfonyl azide in the presence of base. [10] [11]
The classic [13] [14] click reaction is the copper-catalyzed reaction of an azide with an alkyne to form a 5-membered heteroatom ring: a Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC). The first triazole synthesis, from diethyl acetylenedicarboxylate and phenyl azide, was reported by Arthur Michael in 1893. [ 15 ]
Enone–alkene cycloadditions often suffer from side reactions, e.g. those associated with the diradical intermediate. These side reactions can often be minimized by a judicious choice of reaction conditions. Dissolved oxygen is avoided since it is photoreactive. A variety of solvents can be used.
Like the expansion reaction this proceeds with an electron donating group aiding in the migration. Contraction reactions of one ring can be coupled with an expansion of another to give an unequal bicycle from equally sized fused ring. These cationic rearrangements have found use to synthesize the cores of complex molecules. [21]