Note 2.The reaction of esters with NaBH4is extremely slow. However, lithium borohydride (LiBH4) will successfully reduce esters, owing to the greater Lewis acidity of the lithium ion that helps to activate the carbonyl oxygen towards attack. (See article –Acid Catalysis In Addition-Elimination ...
tofCeCl3.砀ereactionWascompletedwithi n24hoursatambienttemperatureandshowh ighfunctionalgroupcompatibilityandch emoselectivity.Functionalitiessuchas halogen,nitro,methoxylandhydroxylgro upsinthearomaticring,underwentcleanr eductionoftheesterfunctionality.Weal sostudiedthereactionmechanism.Anobvi oushydrogenevolutionocc...
6、s and ketones to alcohols 1 and imines 2 or iminium salts 3 to amines with protic solvents 4. The carboxylic acids, esters, amides and nitriles are more resistant towards NaBH41. How- ever, the reactivity of NaBH4can be enhanced by carrying out the reaction in the presence of certain...
The reaction conditions tolerate various functional groups, allowing highly chemoselective reactions in the presence of halide, ester, alkyne, alkene and nitrile substituents. Moreover, with a proper selection of the catalyst it is also possible to obtain a good control in the regioselective hydro...
having terminal olefinic unsaturation by treating with the reaction product of a borane source with from 0.5 to 1.8 equivalents of an alkene having a molecular weight of less than 250 per mole of borane or by treating the isobutene polymer with the borane source in the presence of the alkene....
The β-keto ester substrate has two hetero atoms, Br and O of COOCH3 at the β and β′ positions of the ketone carbonyl group, respectively, generating two reaction pathways with opposite enantioselectivity via Br⋯Ru⋯OC and CO⋯Ru⋯OC(OCH3) chelations [13,15]. Another Noyori ...
Which of the following is formed when an aldehyde or a ketone undergoes an addition reaction with an alcohol molecule in the presence of an acid catalyst? a. ester b. ether c. hemiacetal d. alkene An aldehyde contains the...
An efficient and chemoselective deprotection of prenyl ethers of phenols and alcohols with ZrCl4/NaBH4 in DCM was achieved in high yields. The selectivity of prenyl ether deprotection is well demonstrated by carrying out the reaction in the presence of several other ether and ester functionalities.K...