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Structure, Nomenclature, and Symmetry of Diamondoids
Published in Sven Stauss, Kazuo Terashima, Diamondoids, 2017
Diamondoids or diamond hydrocarbons are generally defined as “molecules whose arrangement of C atoms allows total or partial superposition on the diamond lattice.” However, this is true for many hydrocarbons that are not typically associated with diamondoids. Molecules whose structures can be superimposed on the diamond lattice include, for example, cyclohexane, decalin, simple alkanes (including methane), and also structures close to the diamond lattice such as cyclodecane, and bicyclo[3.3.1]nonane, but since they do not include at least one complete adamantane unit, they are considered as nondiamondoids.
Optical spectrum of the cyanoadamantane radical cation
Published in Molecular Physics, 2023
Parker B. Crandall, Viktoria D. Lovasz, Robert Radloff, Simone Stahl, Marko Förstel, Otto Dopfer
First discovered in crude oil extracts, diamondoids are a class of aliphatic, caged hydrocarbons that have evolving applications to nanotechnology, medicine, propulsion, and material science due to their remarkable optical and structural properties [14–16]. The simplest diamondoid, adamantane (Ada), consists of three conjoined cyclohexane rings that form a single cage unit. Higher-order diamondoids are constructed with additional cages, the number of which is described in the Greek prefix of the common name (diamantane, triamantane, etc.). Several laboratory investigations have explored the connection between bulk carbon structures and diamondoids as their precursors. Their cage structure makes diamondoid applications highly tuneable, as not only has the size-dependence of the electronic properties of diamonds been studied [17,18] but also the effects of functionalization [19–21].
Synthesis of novel adamantane-containing dihydropyrimidines utilizing Biginelli condensation reaction
Published in Journal of Sulfur Chemistry, 2023
Mina Abkar Aras, Adeleh Moshtaghi Zonouz
Diamondoids are cage-saturated hydrocarbon molecules and superimposable on the diamond lattice, which can be described as hydrogen-terminated nanodiamonds [1]. Adamantane, C10H16, as the smallest diamondoid, was first isolated in 1933 from crude oil [2] and synthesized chemically in 1941 by Prelog and Steinwerth [3]. Then Schleyer reported simple, efficient, and inexpensive Lewis acid-catalyzed rearrangement of endo-trimethylenenorbornane to adamantine [4]. After Schleyer’s synthesis, the availability of adamantane led to the syntheses of its derivatives and the pharmaceutical studies thereof. Aminoadamantanes constitute the birth of the medicinal chemistry of adamantane derivatives. 1-Aminoadamantane (Amantadine), a well-known antiviral drug, has been used to treat type A Influenza [5]. Antiviral activity of this amine was found gainst Rubella viruses after that thereafter [6]. Until now, eight drugs incorporating the adamantane moiety have been approved and exist in the pharmaceutical market (Figure 1). These drugs are used to treat for the treatment of acne [7], Parkinson’s [8], Alzheimer’s [9], Influenza A [5], and diabetes diseases [10]. Today adamantane motif is used mainly for modification of known drugs through an add-on strategy. The incorporation of the adamantyl moiety into the known pharmacologically active molecules has improved in many cases their pharmacological properties, without increasing toxicity. So add-on strategy resulted in many promising drug candidates incorporating an adamantane moiety [11].
Diamondoid geochemistry of Niger Delta source rocks: implication for petroleum exploration
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020
Akinsehinwa Akinlua, Blessing I. Ibeachusim, Solomon A. Adekola, T.A. Adedosu, Yun Li, Yongqiang Q. Xiong
Diamondoids are a group of highly stable saturated hydrocarbons that have cage-like structures. Adamantane which is a ten-carbon tetracyclic skeleton constitutes the basic unit of diamondoids. The structural framework of diamondoids is to a great extent superimposable on the diamond lattice, which is the reason they are called diamondoids (Balaban and von Schleyer 1978; Mansoori 2007). The exceptional atomic arrangements of diamondoids confer on them their unique properties (Araujo, Mansoori, and Araujo 2012; Araujo et al. 2011). Although, diamond has abiogenic origin (i.e. originated from nonliving matter), diamondoids found in oils have biogenic source. Diamondoids detected in petroleum were formed by reactions that involve hydrocarbon rearrangement that are comparable to clay minerals reactions that occur in source rocks (Katz, Mancini, and Kitchka 2008).