Boron: A key element in radical reactions

Boron derivatives are becoming key reagents in radical chemistry. Here, we describe reactions where an organoboron derivative is used as a radical initiator, a chain-transfer reagent, and a radical precursor. For instance, B-alkylcatecholboranes, easily prepared by hydroboration of alkenes, represent a very efficient source of primary, secondary, and tertiary alkyl radicals. Their very high sensitivity toward oxygen- and heteroatom-centered radicals makes them particularly attractive for the development of radical chain processes such as conjugate addition, allylation, alkenylation, and alkynylation. Boron derivatives have also been used to develop an attractive new procedure for the reduction of radicals with alcohols and water. The selected examples presented here demonstrate that boron-containing reagents can efficiently replace tin derivatives in a wide range of radical reaction

1-Phenacyl-, 1-carbethoxymethyl- and 1-benzyl-4-dimethylaminopyridinium halides: Isolation and use for generating ylide

295-298Active halide containing electron withdrawing group (EWG) α-to halogen readily reacts with 4-dimethylaminopyridine (DMAP) to give stable salt of pyridinium halide (1-6). The reaction between 1-phenacyl-4-dimethylaminopyridinium halide(s) (1 and 2) and aq. NaOH instantaneously generates 4-dimethylaminopyridinium-1-(2'-hydroxy-2'-phenyl)vinylide 7 as brownish yellow stable crystalline solid which is reported for the first time. Whereas, the other compounds 3-6 do not generate such type of ylide under identical experimental conditions

An Interventional Study Comparing the Memory Retention of Verbal & Pictorial Materials among MMMC Students

Aims: To compare the effectiveness of pictorial against verbal materials in memory retention among medical students. Study Design: Crossover randomized controlled trial. Place and Duration of Study: This study was conducted in Melaka-Manipal Medical College, Muar, Johor, Malaysia in April 2016. Methodology: 38 right-handed medical students of Melaka-Manipal Medical College were volunteers and participants were divided into two groups equally via simple random sampling. One group of participants were to recall pictures shown first followed by words while the other group of participants were to recall words first followed by pictures. All the pictures and words shown were of everyday objects. Data were analysed using Epi Info version 7. Results: There was a significant difference of memory retention between pictures and words (P-value =; p < 0.05) and of memory accuracy (P-value; p < 0.05). For memory retention, both groups were found to have higher scores for pictures than words as both groups obtained a mean score of 11.3 and 13.4 respectively for the pictures and 9.7 and 11.1 respectively for words. For memory accuracy, pictures were found to be recalled better than words as the mean scores for the pictures are higher than words in both groups. Conclusion: Information in the form of pictures should be more utilized in medical schools so that medical students can have better memory retention which in turn will lead to better academic performances