Carborane-containing organophosphorus compounds. Synthesis and properties

Abstract

This work was concerned with the simultaneous measurement of the combination coefficients b and 70, between small ions and aerosol particles and between small ions and uncharged aerosol particles respectively, for different particle radii.The ion-ion mutual repulsion coefficient y was first evaluated from 14 plots of small ion decay in an aerosol-free mylar vessel, which gave a mean experimental value of 2.39 (k 0.14) x 10-8 cm3 s-1.The decay of ions in the presence of aerosol particles in the mylar vessel was recorded and compared with a family of computed theoretical ion-aerosol decay curves to determine b. 70 could then be determined from the concentration of uncharged nuclei present. In the ten experiments carried out b ranged from 0.50 to 2 . 2 4~ 10-8 cm3 s-1 and 70 ranged from 0.33 to 2-39 x 10-6 cm3 s-1, for corresponding radii of 1.26 and 4.0 x 10-6 cm.Satisfactory agreement was found between the b and 70 versus radius results and various theoretically computed values. Possible reasons for discrepancies between theory and experiment are indicated.

Boron derivatives of dithiophosphoric acids

“…2-(O,OЈ-Dialkyl and alkylene dithiophosphato)-1,3,2-dioxaborinanes have been prepared by the reactions of the corresponding dithiophosphoric acids or their ammonium salts with 2-chloro-1,3,2-dioxaborinanes or with trimethylaminoboranes [1,2]. O-Ethyl-S,SЈ-bis(o-carborane-9-yl)dithiophosphate, -trithiophosphate, and -diphenyldithiophosphinate have also been obtained by addition of elemental sulfur to the corresponding (o-carborane-9-yl)thiophosphite, -dithiophosphite, and -diphenyldithiophosphinite, respectively [3][4][5][6][7]. In this article, an alternative and efficient method is presented for the synthesis of S-boron derivatives of dithiophosphoric acids directly from phosphorus sulfide (P 4 S 10 ).…”

“…There is considerable interest in compounds containing the P(S)SB structural fragment [1][2][3][4][5][6][7] due to their potential biological activity and similarly in other boron derivatives of pentavalent phosphorus [6], because of their high reactivity [1,4,6] and their use as synthetic intermediates in the preparation of other new classes of organothiophosphorus compounds [4,6]. Boron dithiophosphates containing the P(S)SB linkage have recently been studied.…”

Synthesis and Molecular Structure of a Superbulky Tertiary Phosphine: Bis[2-phenyl-1,2-dicarba-closo-dodecaboran-1-yl(12)]phenylphosphine

“…In the course of our investigations of dicarbac/oso-dodecaborane( 12)-containing organophos phorus compounds [3], we prepared 1-chlorophenylphosphino-2-phenyl-1,2-dicarba-c/oso-dodecaborane(12) (1) according to the literature proce dure by reaction of dichlorophenylphosphine with one equivalent of l-lithium-2-phenyl-l,2-dicarba-* Reprint requests to Prof. Dr. E. Hey-Hawkins. c/ow-dodecaborane(12) [2].…”

Carborane-derived diphosphites: New ligands for Pd-catalyzed allylic amination

“…Pesticide, bactericide and ferment-inhibition properties of the compounds were also known [2,3]. Despite the encouraging performance of many achiral carborane organophosphorus ligands, especially phosphines [4,5], chiral phosphorus derivatives of carboranes are rare and represented only by our recent work related to the synthesis and first successful application of chiral phosphite derivatives of carboranes in the asymmetric hydrogenation of prochiral olefins (up to 99.8% ee) [6,7]. Encouraged by excellent enantioselectivities in the asymmetric hydrogenation processes and motivated by our continuing efforts in the design of novel chiral carboranylphosphite ligands, we have prepared a series of sterically congested carborane-phosphite derivatives for an application in other important asymmetric catalytic transformations, namely Pd-catalyzed allylic substitution.…”