New Dimensions in Rongalite Chemistry: The Land of Opportunities in Organic Synthesis and Material Sciences

Abstract

Rongalite, first time reported in the chemical structure in 1905, also known as bruggolite or sodium formaldehyde sulfoxylate, having good solubility and stability in organic media, is not only a cheap and commercially available (in kg amount) reagent with a range of industrial applications for instance emulsion polymerization, an excellent decolouring agent, antioxidant in pharmaceutical development, and an antidote for heavy metals, but also used as an effective regents in a plethora of organic reactions particularly in redox reactions as a powerful reducing agent. More interestingly, in recent years, it has also shown its impact in material sciences for the preparation of CdTe, CoTe2, and Ag2Se thin films, nanowire networks, hollow nanospheres, copper nanoparticles (Cu‐Nps), CdTe‐quantum dots and so forth. Keeping in mind the importance of this vital reagent in both organic chemistry as well as in material sciences, herein I intended to report the recent developments along with a brief overview of old literature wherever necessary to showcase the utility of this valuable reagent. This particular review article not only covers the applications of this environmentaly benign reagent in organic synthesis but also its usefulness in material sciences in particular nanosciences has been exposed for the first time.

Rongalite in PEG-400 as a general and reusable system for the synthesis of 2,5-disubstituted chalcogenophenes

“…In a similar way, the synthesis of 2,5-diphenyltellurophene ( 4a ) was also investigated (Table 3, entries 7–11). To our delight, when 1a was submitted to the dark purple solution (indicative of an in situ Te 2− species) 36 produced by the combination of rongalite, KOH and Te 0 in PEG-400, 4a was obtained in 94% yield at 100 °C (Table 3, entry 9), under the same optimized stoichiometric relationship established for the synthesis of 3a (Table 3, entry 4), and this yield represents a remarkable advance when compared with conventional Te 0 reductive systems available for this kind of transformation. 33 Interestingly, when the reaction temperature was raised to 130 °C (Table 3, entry 10), product 4a was only obtained in 52% yield and the respective starting material 1a was not completely consumed, possibly indicating a thermal instability of the Te 2− species at this reaction temperature.…”

“…Considering the wide applications of 2,5-disubstituted chalcogenophenes and our continued interest in the synthesis of organochalcogen compounds, 32,34 d ,35 herein we report rongalite/PEG-400 as a useful and environmentally benign system for generating reactive Y 2− (Y = S, Se or Te) species from their elemental chalcogens, in order to provide a general and environmentally benign protocol for the synthesis of 2,5-disubstituted chalcogenophenes from 1,3-butadiynes (Scheme 1). Rongalite (sodium hydroxymethanesulfinate) is a safe, non-toxic and cheap reagent with recognized reducing properties, 36 which has been explored in organochalcogen chemistry as a reducing agent of Y 0 (Y = Se, Te) 37 and diorganoyl dichalcogenides, 38 under operationally simple reaction conditions. Likewise, PEG-400 is a non-toxic, biodegradable and inexpensive solvent that have been successfully applied in several organic transformations 39 and in organochalcogen chemistry, 40 which was recently identified as a suitable green reaction media for reducing elemental chalcogens into their nucleophilic species.…”

Transition metal-free functionalization of 2-oxindolesviasequential aldol and reductive aldol reactions using rongalite as a C1 reagent

“…19 Kotha and co-workers widely used rongalite in the organic synthesis and named it as a green reagent. 20,21 It acts as a super electron donor, 22,23 and a source of the C1 unit and sulfoxylate dianion (SO 2 2− ). 24–31 Recently, the reductive aldol reaction, which is one of the modified versions of the aldol reaction, has become a promising method for organic synthesis.…”

Interaction of Sodium Selenite With Sodium Hydroxymethanesulfinate and Thiourea Dioxide in Aqueous Solutions

“…Основным маршрутом восстановления селенита in vivo является его реакция с биологическими тиолами [12][13][14]; недавно доказано образование тиол-S-селенита (RS-SeO2 -) в ходе этой реакции [15]. Однако механизм редокс превращений селенита при его взаимодействии с другими серосодержащими восстановителями изучен недостаточно, а реакции с такими известными и широко применяемыми соединениями, как гидроксиметансульфинат натрия (ГМС, ронгалит, HOCH2SO2Na) и диоксид тиомочевины (ДОТМ, (NH2)2CSO2) [16][17][18][19][20][21], не исследованы вообще (взаимодействие селена с ГМС изучено в работе [22]). В настоящей работе изучена реакция восстановления селенита гидроксиметансульфинатом натрия и диоксидом тиомочевины.…”