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A novel photoresponsive and fully conjugated N‐heterocyclic carbene (NHC) has been synthesized that combines the excellent photophysical properties of arylazopyrazoles (AAPs) with an NHC that acts as a robust surface anchor (AAP‐BIMe). The formation of self‐assembled monolayers (SAMs) on gold was proven by ToF‐SIMS and XPS, and the organic film displayed a very high stability at elevated temperatures. This stability was also reflected in a high desorption energy, which was determined by temperature‐programmed SIMS measurements. E‐/Z‐AAP‐BIMe@Au photoisomerization resulted in reversible alterations of the surface energy (i.e. wettability), the surface potential (i.e. work function), and the conductance (i.e. resistance). The effects could be explained by the difference in the dipole moment of the isomers. Furthermore, sequential application of a dummy ligand by microcontact printing and subsequent backfilling with AAP‐BIMe allowed its patterning on gold. To the best of our knowledge, this is the first example of a photoswitchable NHC on a gold surface. These properties of AAP‐BIMe@Au illustrate its suitability as a molecular switch for electronic devices.

The 1,2-aminoalcohol motif is one of the most prevalent structural components found in high-value organic molecules including pharmaceuticals and natural products. Generally, their preparation requires pre-functionalised substrates and manipulations of one functional group at a time to achieve the desired regioisomer. Herein, we describe a metal-free photosensitisation protocol for the installation of both amine and alcohol functionalities into alkene feedstocks in a single step. This approach is enabled by the identification of oxime carbonate as a suitable bifunctional source of both oxygen-and nitrogen-centred radicals for addition across alkenes with complementary regioselectivity compared to Sharpless aminohydroxylation. Use of orthogonal protection for amine and alcohol functionalities enables direct synthetic diversifications of one functional handle without influencing the other. With the use of readily available starting materials, convergent synthesis and mild reaction conditions, this process is well suited for use in various synthetic endeavors.The vicinal aminoalcohol motif is one of the most abundant structural units in natural products, pharmaceuticals, agrochemicals and privileged ligands. [1][2][3] Synthetic routes to this motif rely typically on multistep, iterative manipulations of functional groups to introduce both amine and alcohol functionalities in their desired positions. [4][5][6] Usually transition metal-catalysed directed β-C-H functionalisation of alcohols or amines offers a synthetic alternative with the necessity of a preinstalled directing group. [7][8][9][10] Nevertheless, all these approaches involve manipulation of one functional group at a time (Fig. 1a). By comparison, aminohydroxylation of alkenes is the most straightforward yet powerful approach for the synthesis of 1-amino-2-alcohols allowing simultaneous introduction of both functionalities into the molecule in a single step, as pioneered by Sharpless. 11,12 The generality of this approach however is often plagued by poor regioselectivity and the need for N-haloamides. 13 The use of a similar concept to synthesise 2-amino-1-alcohol skeleton requires a complete regioselectivity switch and remains a challenge to date (Fig. 1b). 14,15 So far, transient N-centred radical initiated aminohydroxylation strategy has been exploited in different intramolecular cyclisation context through ingenious substrate design to generate 2-amino-1-alcohol framework. [16][17][18][19] Clearly, lack of substrate generality and intramolecular nature of these transformations obviates there widespread use. In this regard, Yoon has elegantly utilized high strain of oxaziridine ring in aminal synthesis with analogous regioselectivity. [20][21][22] However, the requirement for initial radical attack by the alkene substrate to the copper-activated oxaziridine limits the use of unactivated alkenes in this aminohydroxylation approach. Alternatively, a two-step aziridination of alkene followed by nucleophilic ring opening can also deliver a similar regiosel...

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Herein, we report the redox-neutral, intermolecular, and highly branch-selective amidation of allylic CÀHb onds enabled by Cp*Ir III catalysis.Avariety of readily available carboxylic acids were converted into the corresponding dioxazolones and efficiently coupled with terminal and internal olefins in high yields and selectivities.M echanistic investigations support the formation of anucleophilic Ir III -allyl intermediate rather than the direct insertion of an Ir-nitrenoid species into the allylic CÀHbond.

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Herein, we describe the formation of quaternary carbon centers with excellent diastereoselectivity via a strain-release protocol. An organometallic species is generated by Cp*Rh­(III)-catalyzed C–H activation, which is then coupled with strained bicyclobutanes (BCBs) and a prochiral carbon electrophile in a three-component reaction. This work illustrates a rare example of BCBs in transition metal catalysis and demonstrates their broad potential to access novel reaction pathways. The method developed exhibits ample functional group tolerance, and the products can be further transformed into valuable α-quaternary β-lactones. Preliminary mechanistic investigations suggest a twofold C–C bond cleavage sequence involving σ-bond insertion and an ensuing β-carbon elimination event.

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