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An efficient Mn-catalyzed aerobic oxidative hydroxyazidation of olefins for synthesis of β-azido alcohols has been developed. The aerobic oxidative generation of azido radical employing air as the terminal oxidant is disclosed as the key process for this transformation. The reaction is appreciated by its broad substrate scope, inexpensive Mn-catalyst, high efficiency, easy operation under air, and mild conditions at room temperature. This chemistry provides a novel approach to high value-added β-azido alcohols, which are useful precursors of aziridines, β-amino alcohols, and other important N- and O-containing heterocyclic compounds. This chemistry also provides an unexpected approach to azido substituted cyclic peroxy alcohol esters. A DFT calculation indicates that Mn catalyst plays key dual roles as an efficient catalyst for the generation of azido radical and a stabilizer for peroxyl radical intermediate. Further calculation reasonably explains the proposed mechanism for the control of C-C bond cleavage or for the formation of β-azido alcohols.

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Aliphatic alcohols are common and bulk chemicals in organic synthesis. The site-selective functionalization of non-activated aliphatic alcohols is attractive but challenging. Herein, we report a silver-catalyzed δ-selective Csp3-H bond functionalization of abundant and inexpensive aliphatic alcohols. Valuable oximonitrile substituted alcohols are easily obtained by using well-designed sulphonyl reagents under simple and mild conditions. This protocol realizes the challenging δ-selective C–C bond formation of simple alkanols.

A novel and efficient Fe-catalyzed direct C-H amination (NH ) of arenes is reported using a new redox-active aminating reagent. The reaction is simple, and can be performed under air, mild, and redox-neutral conditions. This protocol has a broad substrate scope and could be used in the late-stage modification of bioactive compounds. Mechanistic studies demonstrate that a radical pathway could be involved in this transformation.

The catalytic decarboxylative nitrogenation of aliphatic carboxylic acids for the synthesis of alkyl azides is reported. A series of tertiary, secondary, and primary organoazides were prepared from easily available aliphatic carboxylic acids by using K2S2O8 as the oxidant and PhSO2N3 as the nitrogen source. The EPR experiment sufficiently proved that an alkyl radical process was generated in the process, and DFT calculations further supported the SET process followed by a stepwise SH2 reaction to afford azide product.

The first example of Pd -catalyzed enantioselective C-H olefination with non-chiral or racemic sulfoxides as directing groups was developed. A variety of chiral diaryl sulfoxides were synthesized with high enantioselectivity (up to 99 %) through both desymmetrization and parallel kinetic resolution (PKR). This is the first report of Pd -catalyzed enantioselective C(sp )-H functionalization through PKR, and it represents a novel strategy to construct sulfur chiral centers.

Control of selectivity is one of the central topics in organic chemistry. Although unprecedented alkoxyl-radicalinduced transformations have drawn a lot of attention, compared to selective CÀH activation, selective radical OÀH activation remains less explored. Herein, we report a novel selective radical O À H activation strategy of diols by combining spatial effects with proton-coupled electron transfer (PCET). It was found that DMSO is an essential reagent that enables the regioselective transformation of diols. Mechanistic studies indicated the existence of the alkoxyl radical and the selective interaction between DMSO and hydroxyl groups. Moreover, the distal C À C cleavage was realized by this selective alkoxylradical-initiation protocol. The selective transformation of hydroxyl (OH) groups in diand polyols is a frequently encountered problem in organic synthesis, in contexts ranging from simple alcohol transformations to the preparation of highly functionalized natural products. [1] Despite the importance of this issue, strategies for the selective O À H activation are rare compared to the fastgrowing studies on selective CÀH activation. [2] The classic methods for selective activation of one hydroxyl in diols involve ionic transformations by steric regulation or based on special hydrocarbon structure. [3] Unlike traditional ionic alcohol transformations involving nucleophilic substitution/ addition, [4] oxidation [5] and elimination [6] of hydroxyls, the alkoxyl radical induced transformations have drawn more attention with the discovery of unprecedented strategies for the generation of alkoxy radicals from alcohol without the need for pre-activation. [7] The OÀH radical processes greatly enlarged the reaction types of alcohols either with alkoxyl radical induced b scission [8] or hydrogen abstraction. [9, 10] However, to the best of our knowledge, the general methods for the alkoxyl radical induced distal CÀC cleavage remains unexplored (Scheme 1 a). Moreover, the realized OÀH radical transformations are limited to the activation of mono-ols, so far, there is a lack of selective radical O À H activation due to the almost identical bond-dissociation energy between two hydroxyls in diols (% 105 kcal mol À1) [11] (Scheme 1 b). To address this problem, we paid our attention to the strategy of proton coupled electron transfer (PCET), which was reported that a Brønsted base and an oxidant can synergistically remove a proton and an electron from the substrate to afford a free radical (Scheme 1 c). [12] Recently, Knowles and co-workers significantly achieved the O À H bond homolysis through PCET. [13] Inspired by these reports, we hypothesized that if we could find a proper Brønsted or Lewis base that can selectively form a hydrogen bond with one hydroxyl in diols, we would have a chance to selectively activate one O À H bond and realize the selective alkoxyl radical transformation of diols (Scheme 1 d). Scheme 1. Selective hydroxyl activation of diols.