| Reference | [1]. Molecules. 2018 Jun 15;23(6):1457. doi: 10.3390/molecules23061457.<br />
Phosphorus Pentachloride Promoted gem-Dichlorination of 2'- and 3'-Deoxynucleosides.<br />
da Paixao Soares F(1), Groaz E(2), Herdewijn P(3).<br />
Author information: (1)Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, 3000 Leuven, Belgium. [email protected]. (2)Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, 3000 Leuven, Belgium. [email protected]. (3)Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, 3000 Leuven, Belgium. [email protected].<br />
Halogen substitution at various positions of canonical nucleosides has generated a number of bioactive structural variants. Herein, the synthesis of two unique series of sugar modified nucleosides bearing a gem-dichloro group is presented. The synthetic plan entails the controlled addition of phosphorus pentachloride to suitably protected 2′- or 3′-ketodeoxynucleoside intermediates as the key step, facilitating the rapid construction of such functionalized molecules. Under the same reaction conditions, the highest chemoselectivity was observed for the formation of 2′,2′-dichloro-2′,3′-dideoxynucleosides, while a competing 2′,3′-elimination process occurred in the case of the 3′,3′-dichloro counterparts.<br />
DOI: 10.3390/molecules23061457 PMCID: PMC6100136 PMID: 29914115<br />
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[2]. Langmuir. 2017 Sep 5;33(35):8766-8773. doi: 10.1021/acs.langmuir.7b00518. Epub 2017 Jun 14.<br />
Phosphorus Pentachloride Initiated Functionalization of Silicon Nanocrystals.<br />
Islam MA(1), Mobarok MH(1), Sinelnikov R(1), Purkait TK(1), Veinot JGC(1).<br />
Author information: (1)Department of Chemistry, University of Alberta , 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada.<br />
Phosphorus pentachloride (PCl5) has long been used to chlorinate hydrocarbons. It has also been applied in silicon surface chemistry to facilitate alkylation via a two-step halogenation/Grignard route. Here we report a study of the reaction of PCl5 with hydride-terminated silicon nanocrystals (H-SiNCs). An examination of the reaction mechanism has allowed us to establish a functionalization protocol that uses PCl5 as a surface radical initiator to introduce alkyl and alkenyl moieties to the surface of H-SiNCs. The reaction proceeds quickly in a single step, at room temperature and the functionalized silicon nanocrystals retained their morphology and crystallinity. The resulting materials exhibited size-dependent photoluminescence that was approximately 3× as bright as that observed for thermally hydrosilylated SiNCs. Furthermore, the absolute PL quantum yield (AQY) was more than double. The high AQY is expected to enable SiNCs to compete with chalcogenide-based quantum dots in various applications.<br />
DOI: 10.1021/acs.langmuir.7b00518 PMID: 28581767<br />
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[3]. Inorg Chem. 2006 Jul 24;45(15):6073-82. doi: 10.1021/ic060681k.<br />
Chemistry of the silica surface: reaction with phosphorus pentachloride.<br />
Zheng S(1), Feng JW, Diverdi JA, Maciel GE.<br />
Author information: (1)Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA.<br />
Solid-state 31P and 29Si NMR experiments, with Magic-Angle Spinning (MAS), were used to elucidate the chemistry that occurs when silica gel is treated with phosphorus pentachloride. A low-loading regime (in which the molar ratio of initial PCl5 to surface silanols sites is <<1) and a high-loading regime (in which this ratio is approximately 1) were examined. For each regime, the results for limited and intentional exposure to moisture are presented. The occurrence of phosphorus bridging between two adjacent silanols sites is observed. Bridging structures based on Si-O-P-O-P-O-Si linkages are also indicated.<br />
DOI: 10.1021/ic060681k PMID: 16842016<br />
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[4]. J Res Natl Bur Stand A Phys Chem. 1974 May-Jun;78A(3):375-386. doi: 10.6028/jres.078A.021.<br />
Enthalpy of Formation of Phosphorus Pentachloride; Derivation of the Enthalpy of Formation of Aqueous Orthophosphoric Acid.<br />
Schumm RH(1), Prosen EJ(1), Wagman DD(1).<br />
Author information: (1)Institute for Materials Research, National Bureau of Standards, Washington, D.C. 20234.<br />
When chlorine (real gas, 980 mmHg) combines with white (α) phosphorus to form phosphorus pentachloride at 24.89 °C, 3986.3 ± 2.7 J of heat are liberated per gram of stoichiometrically equivalent Mg2P2O7. This value was determined by a dead-ended flow system in an electrically calibrated isoperibol calorimeter. Correction was made for the formation of up 10 one mol percent PCl3 in the products; no other impurities were found. From this value, the standard (25 °C, ideal gas) enthalpy of formation of PCl5(c) is calculated to be -443.85 ± 0.30 kJ/mol, -106.08 ± 0.07 kcal/mol. When this figure is combined with a recent determination of the enthalpy of hydrolysis of PCl5(c), the standard enthalpy of formation of H3PO4 (aq, 100 H2O) is calculated to be -1296.5 ± 1.5 kJ/mol, in good agreement with two other values which involve the formation and hydrolysis of P4O10 (hex). A "best value" is suggested: ΔH f° (H3PO4, 100 H2O) = -1295.8 ± 1.3 kJ/mol, -309.7 ± 0.3 kcal/mol.<br />
DOI: 10.6028/jres.078A.021 PMCID: PMC6742818 PMID: 32189788<br />
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[5]. Steroids. 1975 Oct;26(4):470-6. doi: 10.1016/0039-128x(75)90066-5.<br />
The reaction of 5alpha-cholestan-6alpha-ol with phosphorus pentachloride and with thionyl chloride.<br />
Shoppee CW, Lundberg RD.<br />
GC analysis of the reaction product of 5alpha-cholestan-6alpha-ol and phosphorus pentachloride indicated the presence of 6alpha-chloro-5alpha-cholestane, 6beta-chloro-5alpha-cholestane, 5,6beta-dichloro-5alpha-cholestane, and traces of cholest-5-ene; a computerised GC-MS system furnished visual reproductions of the gas chromatograms, but failed to yield corresponding mass chromatograms because of decomposition of the chlorides in the molecular separator. GC analysis of the reaction product of 5alpha-cholestan-6alpha-ol and thionyl chloride showed the formation of 6alpha-chloro-5alpha-cholestane, cholest-5-ene, 5-chloro-5alpha-cholestane, and traces of four unidentified substances, whilst the GC-MS system furnished visual reproductions of the gas chromatograms, but again failed to yield corresponding mass chromatograms.<br />
DOI: 10.1016/0039-128x(75)90066-5 PMID: 1202663
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