42600-58-8Relevant articles and documents
A small bifunctional chelator that modulates Aβ42 aggregation
Zhang, Chaofeng,Gomes, Luiza M.F.,Zhang, Tonglu,Storr, Tim
, p. 78 - 82 (2018/01/12)
Multifunctional compounds that can modulate amyloid-β (Aβ) aggregation and interact with metal ions hold considerable promise as therapeutic agents for Alzheimer's disease (AD). Using the copper-catalyzed azide-alkyne cycloaddition reaction, a novel bifun
Formamides as Lewis Base Catalysts in SNReactions—Efficient Transformation of Alcohols into Chlorides, Amines, and Ethers
Huy, Peter H.,Motsch, Sebastian,Kappler, Sarah M.
supporting information, p. 10145 - 10149 (2016/08/16)
A simple formamide catalyst facilitates the efficient transformation of alcohols into alkyl chlorides with benzoyl chloride as the sole reagent. These nucleophilic substitutions proceed through iminium-activated alcohols as intermediates. The novel method, which can be even performed under solvent-free conditions, is distinguished by an excellent functional group tolerance, scalability (>100 g) and waste-balance (E-factor down to 2). Chiral substrates are converted with excellent levels of stereochemical inversion (99 %→≥95 % ee). In a practical one-pot procedure, the primary formed chlorides can be further transformed into amines, azides, ethers, sulfides, and nitriles. The value of the method was demonstrated in straightforward syntheses of the drugs rac-Clopidogrel and S-Fendiline.
Halogenation of benzyl- and (heteroaromatic methyl)cobaloximes: Direct competition between ring halogenation and cobalt-carbon bond cleavage
Gupta,Kumar, Manoj,Roy, Sujit
, p. 11 - 18 (2008/10/08)
(4-Acetamidobenzyl)- and (4-(dimethylamino)benzyl)cobaloximes react rapidly with low concentrations of chlorine and bromine in acetic acid or chloroform at room temperature under nitrogen. Both ring-halogenated organometallic products and direct Co-C cleavage products are formed. However, (4-methoxybenzyl)cobaloxime forms 4-methoxy-2-halotoluene as the exclusive product. (3-Methylbenzyl)cobaloxime undergoes a substantial proportion of ring substitution by both Br2 and Cl2 in competition with the cleavage of the Co-C bond. (3-Methoxybenzyl)cobaloxime forms only the ring-substituted organometallic product. A remarkable difference in reactivity between 2- and 3-isomers of the (thienylmethyl)- and (furylmethyl)cobaloximes is observed; for example, Co-C cleavage is the primary process in furfuryl- and (2-thienylmethyl)cobaloximes whereas ring halogenation occurs much faster in the 3-isomer. The results are discussed in terms of a σ-π delocalization phenomenon by which the electronic effect of a substituent in the benzyl group is effectively transmitted to the Co-C bond reactivity. The substituent effect of the metallomethyl group -CH2Co(dmgH)2py is found to be more than that of the methoxy group. The mechanism of the Co-C cleavage is described.
