Nickel-Catalyzed Formic Acid Reductions. A Selective Method for the Reduction of Nitro Compounds

Abstract

Generalized Zero-Shot Learning (GZSL) has emerged as a pivotal research domain in computer vision, owing to its capability to recognize objects that have not been seen during training. Despite the significant progress achieved by generative techniques in converting traditional GZSL to fully supervised learning, they tend to generate a large number of synthetic features that are often redundant, thereby increasing training time and decreasing accuracy. To address this issue, this paper proposes a novel approach for synthetic feature selection using reinforcement learning. In particular, we propose a transformer-based selector that is trained through proximal policy optimization (PPO) to select synthetic features based on the validation classification accuracy of the seen classes, which serves as a reward. The proposed method is model-agnostic and data-agnostic, making it applicable to both images and videos and versatile for diverse applications. Our experimental results demonstrate the superiority of our approach over existing feature-generating methods, yielding improved overall performance on multiple benchmarks.

New Synthetic Routes for the Preparation of 2-Amino-3-hydroxy-1,4-naphthoquinone

“…This methodology has been reported to selectively reduce aromatic nitro compounds. 11 The second route involves the reduction of 1 with Sn/HCl under reflux 12 which gives product 2 in 78% yield and 4-nitroaniline after the same work out procedure. The overall yields of product 2 from both routes are quite good (78%-82%), when compared to those described previously (53%-45%).…”

Synthesis, molecular modelling and CYP24A1 inhibitory activity of novel of ( E )- N -(2-(1 H -imidazol-1-yl)-2-(phenylethyl)-3/4-styrylbenzamides

“…The 2-amino-1-phenylethanol derivatives (5) were prepared in two steps, first thenitroalcohols (4) were prepared from the corresponding benzaldehyde (3) and nitromethane by the Henry reaction employing either NaOH, Amberseep 900 (OH) or triethylamine as the base 26,27,28 . Reduction of the -nitroalcohols to the corresponding amino derivatives (5) was achieved using a slurry of Raney nickel and formic acid under H2 atmosphere at room temperature for 6 h (Scheme 1) 29 . The 4-styrylbenzoic acids (8) were conveniently prepared from the corresponding alkene (6) and 4-bromobenzoic acid (7) under Heck reaction conditions (Scheme 1).…”

Reaction of Nitromethane with Cinnamoyl Derivatives of Cyclic β-dicarbonyl Compounds. Application to the Synthesis of 2(3)-(4-aryl-pyrrolidin-2-ylidene)-1,3(2,4)-diones*

“…This system is found to be compatible with many functionalities including ketones [39]. Reduction of compounds 11, 13-15 by this system at room temperature leads to 4-arylpyrrolidin-2-ylidene derivatives 16, 18-20 in 47-93% yield ( Table 3).…”

“…For the selective reduction of nitro group in the derivatives 11-15, the use of Raney nickel in the mixture of methanol and 90% formic acid [39] proved to be the most effective. This system is found to be compatible with many functionalities including ketones [39].…”