A Novel Indium‐Boron Amorphous Alloy Mediator for Barbier‐Type Carbonyl Allylation in Aqueous Medium

Abstract

A novel indium-boron (In-B) amorphous alloy was prepared by chemical reduction of indi-À ] in aqueous solution and was applied to the water-medium Barbier-type allylation reactions. A variety of allyl halides could be efficiently added to aldehydes or ketones in water. Additionally, the as-prepared In-B exhibits much higher activity than the commercial In powder and the crystallized In-B owing to the high surface area, the unique amorphous alloy structure, and the high electron density on the In active sites resulting from the strong electronic interaction between the metal In and the alloying B. The yield of target product over the In-B amorphous alloy was similar to that obtained on the homogeneous Pd(II) organometallic catalyst, showing good potential in practical application.

Synthesis and catalysis of chemically reduced metal–metalloid amorphous alloys

“…Li and coworkers reported that the In-B amorphous alloy showed higher activity than the In powder in allylation of benzaldehyde in water, and maintained a high selectivity of 98% (Scheme 15). 305 They further demonstrated that In-B is active for the Barbier-type allylation of substituted benzaldehydes and a number of allylic halides with selectivities Z 97% at conversions Z 94%. In Barbier-type allylation of acetophenone on In-B, allyl bromide showed similar allylation result to the expensive allylboronate, giving the 2-phenyl-4-penten-2-ol selectivity of 94% at the conversion of 90%.…”

Chapter 4. Preparation and catalytic applications of amorphous alloys

“…Recently, we reported the first synthesis of In-B amorphous alloy NPs by chemical reduction method. 47 The average particle size was about 8.5 nm (Fig. 8).…”

Skeletal Ni Catalysts Prepared from Amorphous Ni–Zr Alloys: Enhanced Catalytic Performance for Hydrogen Generation from Ammonia Borane

“…The utilization of amorphous alloys as catalysts has gained the attention of many scientists, due to their discriminating states. For instance, it has been reported that amorphous alloys shows higher catalytic activities than crystalline alloys in the hydrogenation, oxidation, and alkylation reactions . According to these studies, the completely disordered atomic arrangement of amorphous alloys contributes significantly to the enhancement of the catalytic activities.…”

“…For instance, it has been reported that amorphous alloys shows higher catalytic activities than crystalline alloys in the hydrogenation,o xidation,and alkylation reactions. [4][5][6][7][8][9][10][11][12][13][14] According to these studies, the completely disordered atomica rrangemento fa morphous alloys contributes significantly to the enhancement of the catalytic activities.H owever,f ew researchers have paid attention to the relationship between the catalytic properties and the structural changes that occur during the crystallization process of amorphousa lloys. Amorphous alloys transform into various transitional intermediates tates, such as precrystallizeda nd partly crystallized states upon heating.…”