Selective reduction of mixed anhydrides of carboxylic acids to alcohols using borohydride exchange resin (BER)–nickel acetate

Abstract

Mixed anhydrides of carboxylic acids have been selectively reduced to alcohols with borohydride exchange resin-nickel acetate under mild conditions and in good yields.

In situ silane activation enables catalytic reduction of carboxylic acids

“…10,11 While these reagents are widely used their high reactivity renders many of them air and moisture sensitive and their multi-hydridic nature also generates hazards when quenching reactions. Converting carboxylic acids to activated derivatives, such as benzotriazoles, [12][13][14][15] boronate esters 16,17 or mixed anhydrides [18][19][20][21] allows reduction to alcohols under much milder conditions, allowing greater functional group tolerance but this is achieved at the expense of atom efficiency as stoichiometric activating agents are required. 22 A more atom economical approach involves catalytic hydrogenation using hydrogen gas, [23][24][25][26] however these reactions require harsh reaction conditions such as high temperatures and pressures.…”

Aniline‐Based Disulfide/Aniline Copolymers as a High Energy‐Storage Material

“…[17] The D-201 anion exchange resin (chloride form, 15 g) was added to 150 mL 0.5 mol Á L À1 aqueous sodium borohydride. After stirring for 1 h at room temperature, the resulting BER was washed thoroughly with deionized water until free of excess sodium borohydride, and then it was dried in vacuum oven at 60 8C, and then stored in dryer under nitrogen at room temperature for using.…”

“…The borohydride‐bound ion exchange resin (BER) was prepared by the following method described in the literature 17. The D‐201 anion exchange resin (chloride form, 15 g) was added to 150 mL 0.5 mol · L −1 aqueous sodium borohydride.…”

High‐Speed Reduction of Triarylpyrylium Salts Using Zn(BH4)2/SiO2 as an Efficient and Regiospecific Reducing Reagent

“…e selective reduction is a real challenge in organic synthesis. e selectivity is generally achieved by the use of modi�ed reducing reagents which are formed by the replacement of hydride with sterically bulky substituents or electronwithdrawing groups [1][2][3][4]. us to achieve this goal, currently the use of modi�ed hydride donors has been expanded [5][6][7][8].…”