935-56-8Relevant articles and documents
Schwartz,Moon
, p. 865,868 (1975)
Alkylphosphinites as Synthons for Stabilized Carbocations
Ochmann, Lukas,Kessler, Mika L.,Schreiner, Peter R.
supporting information, p. 1460 - 1464 (2022/03/01)
We present a new acid-free method for the generation of carbocations based on a redox condensation reaction that enables SN1 reactions with a variety of nucleophiles. We utilize readily synthesized phosphinites that are activated by diisopropyl azodicarboxylate to form betaine structures that collapse upon adding a pronucleophile, thereby yielding reactive carbocation intermediates. We also employ this approach for the alkylation of some bioactive molecules.
Copper-Catalyzed Intermolecular Functionalization of Unactivated C(sp3)-H Bonds and Aliphatic Carboxylic Acids
Mao, Runze,Bera, Srikrishna,Turla, Aurélya Christelle,Hu, Xile
supporting information, p. 14667 - 14675 (2021/09/18)
Intermolecular functionalization of C(sp3)-H bonds and aliphatic carboxylic acids enables the efficient synthesis of high value-added organic compounds from readily available starting materials. Although methods involving hydrogen atom transfer have been developed for such functionalization, these methods either work for only activated C(sp3)-H bonds or bring in a narrow set of functional groups. Here we describe a Cu-catalyzed process for the diverse functionalization of both unactivated C(sp3)-H bonds and aliphatic carboxylic acids. The process is enabled by the trapping of alkyl radicals generated through hydrogen atom abstraction by arylsulfonyl-based SOMO-philes, which introduces a large array of C, N, S, Se, and halide-based functional groups. The chemoselectivity can be switched from C-H functionalization to decarboxylative functionalization by matching the bond dissociation energy of the hydrogen atom transfer reagent with that of the target C-H or O-H bond.
Exhaustive One-Step Bridgehead Methylation of Adamantane Derivatives with Tetramethylsilane
Bonsir, Maxime,Davila, Christian,Geerts, Yves,Kennedy, Alan R.
supporting information, p. 5227 - 5237 (2021/10/19)
A methylation protocol of adamantane derivatives was investigated and optimized using AlCl3 and tetramethylsilane as the methylation agent. Substrates underwent exhaustive methylation of all available bridgehead positions with yields ranging from 62 to 86 %, and up to six methyl groups introduced in one step. Scaling-up of the reaction was demonstrated by performing the >40 gram-scale synthesis of 1,3,5,7-tetramethyladamantane with 62 % yield. For several substrates, rearrangements were observed, as well as cleavage of functional groups or Csp3?Csp2 bonds or even cyclohexyl-adamantyl bonds. Based on mechanistic studies, it is suggested that a reactive methylation complex is formed from tetramethylsilane and AlCl3. X-ray diffraction structures of hexamethylated bis-adamantyls reveal elongation or widening of sp3 carbon bonds between adamantyl moieties to 1.585(3) ? and 125.26(9)° due to repulsive H???H contacts.
