Search results
Results from the WOW.Com Content Network
Phenylmagnesium bromide is a strong nucleophile as well as a strong base.It can abstract even mildly acidic protons, thus the substrate must be protected where necessary. It often adds to carbonyls, such as ketones, aldehyde
In many preparations of delicate organic compounds, specific parts of the molecules cannot survive the required reagents or chemical environments. These parts (functional groups) must be protected. For example, lithium aluminium hydride is a highly reactive reagent that usefully reduces esters to alcohols.
The reagent removes pairs of H atoms from organic molecules. The stoichiometry of its action is illustrated by the conversion of tetralin to naphthalene: 2 C 6 Cl 2 (CN) 2 O 2 + C 10 H 12 → 2 C 6 Cl 2 (CN) 2 (OH) 2 + C 10 H 8. The resulting hydroquinone is poorly soluble in typical reaction solvents (dioxane, benzene, alkanes), which ...
p-Methoxybenzyl (PMB) is used as a protecting group for alcohols in organic synthesis (4-Methoxybenzylthiol is used to protect thiols). The p -methoxybenzyl group Strong base such as powdered potassium hydroxide or sodium hydride and p -methoxybenzyl halide (chloride or bromide) [ 14 ] [ 15 ]
Para-methoxybenzyl (PMB) is a commonly used protecting group for alcohols against Fétizon's reagent. [15] As Fétizon's oxidation is a neutral reaction, acid and base sensitive protecting groups are also compatible with the reagent and by products generated.
Initial steps in the Buchner–Curtius–Schlotterbeck reaction mechanism. The reaction is then completed either by the reformation of the carbonyl through an 1,2-rearrangement or by the formation of the epoxide. There are two possible carbonyl products: one formed by migration of R 1 (4) and the other by migration of R 2 (5). The relative ...
Alkylation of the bis-paramethoxybenzyl (pMB) protected 2,5-DKP 1 using the base LHMDS and an alkyl bromide R 1 Br, gave the mono-alkylated derivative 2, which on further alkylation gave the symmetrical trans-disubstituted derivative 3. Enolate akylation at C-3 and C-6
The authors then converted the beta-nitroamines into unprotected 1,2-diamines via a two step procedure. Firstly, the nitro group was reduced to amines using samarium iodide, followed by PMB removal in the presence of ceric ammonium nitrate (CAN). The same group later reported improvements to this methodology and expanded these preliminary ...