A highly efficient catalytic asymmetric alkynylation of prochiral CH2 groups in tetrahydroisoquinoline was developed using copper catalyzed cross-dehydrogenative-coupling of sp3 and sp C–H bonds with the assistance of a photocatalyst and visible light.

The functionalization of α-amino acids and peptides provides the opportunity to tailor the properties of these biomolecules for diverse applications in chemistry and biology. Previous methods for N-modification involve the use of aliphatic alcohols, aldehydes, or halides. Alternatively, phenolic compounds are more desirable alkylating reagents as they constitute the backbone of lignin, making them an attractive bio-renewable resource. Here we report a method to N-modify 17 out of the 20 amino acids with phenol or derivatives, with water as the sole by-product. N-arylation is achieved using 2-cyclohexen-1-one and cyclohexanone as the coupling partners. Notably, phenol is successfully used to N-cyclohexylate α-amino acids and small peptides in excellent yields under bio-compatible conditions without racemization.

The reaction of nitric oxide with benzyl cyanide in the presence of potassium methoxide at low temperature gave the dipotassium salt of a bis-diazeniumdiolate 2 in excellent yield. Two new stereospecific syntheses of E or Z 2-(hydroxyimino)-2-phenylacetonitrile from 2 have been found. The thermodynamics of the E/Z isomerization has been investigated spectroscopically in solution, in the solid state by differential scanning calorimetry (DSC), and theoretically in the gas phase. Evidence of catalysis by NO of E/Z oxime isomerization has been observed.

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Arylamines are commerciallya nd synthetically useful compounds with aw ide variety of applications.T heir preparation has been traditionally achieved using metal-catalyzedC ÀN coupling reactions with aryl halides. In this work, 17 different diarylamines are prepared from phenolsb yu sing ammonium formate as the aminatingr eagent. Phenolicc ompounds are more desirable feedstocks, owing to their availability from lignin, making them valuable biorenewable alternatives to aryl halides. Ammonium formate is found to be aconvenient surrogate for ammonia and au seful aminating reagent for phenols. Diarylamine products are obtained in good to excellent yields while only water and CO 2 are generated as byproducts of the transformation.Arylamines are valuable commodity chemicals, owing to their broad application as antioxidizers and as synthetically relevant buildingblocks. Diphenylamine (DPA) is primarily used as astabilizer for nitrocellulose explosives [1] and the detection of oxidizers, [2] whereas C-alkylated diphenylamines are widely used as antioxidants for the preservation of fruits, [3] oils, [4] and polymers. [5] Further uses of arylamines include being ap recursor for the synthesis of (azo-)dyes, [6] and nonsteroidal anti-inflammatoryd rugs. [7] Additionally,t riphenylamines are important for the preparation of optoelectronic materials. [8] For at horough review on the use of these compounds, please see the reference articles by Drzyzga [9] and Layer. [10] Arylamines are commonly prepared from amine precursors through metal-catalyzedC ÀNc oupling reactions. Methods for the formation of these compounds include the Stille, [11] Chan-Evans-Lam, [12] Ullmann, [13] and Buchwald-Hartwig [14] couplings. In addition, other methods, including P III /P V =Oc atalysis, [15] iodine, [16] sulfonium triflates, [17] various nanoparticle catalysts, [18] and Pd/C catalysis for the formationo fa rylamines from aliphatic substrates, [19] have also been reported. Similard evelopments for the formation of diaryl ethers have also been reported. [20] Phenol can be obtainedf rom naturals ources, as one of the basic units of lignin, making it an attractive biorenewable feed-