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A highly tunable defluorophosphorylation of fluorinated peroxides for the preparation of C3,4-diphosphoryl furans and C4-monophosphoryl furans under conditions with no added transition metals is disclosed.

A simple and practical Cs2CO3-promoted method for the synthesis of 6-nitroindole derivatives from enaminones and nitroaromatic compounds has been developed.

An efficient defluorinative net-[3 + 3]-cyclization strategy for the construction of perfluoroalkyl-substituted pyrimidine derivatives by using a series of perfluoroalkyl alkynes and amidines as starting materials was developed. The present reaction proceeded successfully under transition-metal-free conditions to form two new C–N bonds and a new heterocyclic ring through a sequence of hydroamination, defluorination, and annulation. The desired pyrimidines could be obtained with good functional group tolerance and moderate to good yields. Moreover, the distinctive fluorine effects of perfluoroalkyl substituents are vital for tuning the reactivity of alkynes for the anticipated defluorinative annulation. The pendant π system would lower associated bond dissociation energy significantly compared to that of a nonactivated C(sp3)–F bond.

An efficient palladium-catalyzed direct reductive cross-coupling of aryltrimethylammonium salts with aryl bromides was developed. The reactions proceeded smoothly in the presence of a palladium catalyst, magnesium turnings, LiCl, and TMEDA in THF at room temperature, leading to the corresponding biaryl compounds in moderate to good yields with reasonable functional group tolerance. The one-pot reaction using cheap and readily available aryl bromide as a coupling partner is simple to handle, thereby avoiding the use of pre-prepared organometallic reagents.

A straightforward aerobic oxidative esterification of aryl aldehydes with alcohols has been developed for the synthesis of substituted esters by employing vitamin B1 as a cost-effective, metal-free, and eco-friendly NHC catalyst. Air is used as a green terminal oxidant. The reaction is a useful addition to the existing NHC-catalytic oxidative esterification.

A Selectfluor™-catalyzed oxidative cyclization of ynamides affording oxazolidine-2,4-diones in yields from 69%–94% is described. The reaction is run under air and exhibits excellent chemo-selectivity and functional group compatibility. Preliminary mechanistic studies reveal that the solvent DMSO acts as an oxidant, and the redox reaction of Selectfluor™ with DMSO generates the real active catalyst HBF4in situ.