3739-96-6Relevant academic research and scientific papers
Synthetic and Spectroscopic Investigations Enabled by Modular Synthesis of Molecular Phosphaalkyne Precursors
Transue, Wesley J.,Yang, Junyu,Nava, Matthew,Sergeyev, Ivan V.,Barnum, Timothy J.,McCarthy, Michael C.,Cummins, Christopher C.
supporting information, p. 17985 - 17991 (2019/01/09)
A series of dibenzo-7-phosphanorbornadiene compounds, Ph3PC(R)PA (1-R; A = C14H10, anthracene; R = Me, Et, iPr, sBu), are reported to be capable of thermal fragmentation to generate alkyl-substituted phosphaalkynes (RC≡P) concomitant with triphenylphosphine and anthracene. Facile preparation of these molecular precursors proceeds by treatment of ClPA with the appropriate ylide Ph3P=CHR (2 equiv). For methyl, ethyl, and isopropyl substituents, the phosphaalkyne conversions are measured to be 56-73% in solution by quantitative 31P NMR spectroscopy. In the case of compound 1-Me, the kinetic profile of its spontaneous unimolecular fragmentation is investigated by an Eyring analysis. The resulting 1-phosphapropyne is directly detected by solution NMR spectroscopy and gas phase rotational microwave spectroscopy. The latter technique allows for the first time measurement of the phosphorus-31 nuclear spin-rotation coupling tensor. The nuclear spin-rotation coupling provides a link between rotational and NMR spectroscopies, and is contextualized in relation to the chemical shift anisotropy.
Synthesis and reactivity of an unprecedented osmium(VIII) alkylidene
Martin, Véronique,Blakey, Simon
supporting information; experimental part, p. 6800 - 6803 (2009/04/06)
The synthesis of a family of Os(VIII) alkylidene complexes, the highest oxidation state alkylidenes known to date, and their reactivity toward small organic molecules are reported.
Untersuchungen im Wittig-System nach einem ordnenden Konzept auf der Basis alternativer Prinzipien
Bandmann, Heinz,Bartik, Tamas,Bauckloh, Sylvia,Behler, Ansgar,Brille, Frank,et al.
, p. 193 - 204 (2007/10/02)
Our results show that the stereoselectivity of the Wittig-reaction can be controlled by the variation of substituents in accord with the ORDERING CONCEPT OF ALTERNATIV PRINCIPLES (individual pairs, known and unknown classes of alternatives).The "all-phenyl Wittig-system" having three phenyl groups on phosphorous two in ylid- and aldehyd-position was chosen as a standard for our investigations.Differentiation in ylid-position and compensation on phosphorous and aldehyd-position were observed by the comparison of "patterns".Consequently, most of the selectivity rules of Wittig-reactions can be explained by the differentiation through alternatives in the ylid-position.Inversion or conservation of the "patterns" of measured data points to the variation in structure of starting materials, reaction rates and selectivities.Amount-controls were also described in certain systems.
