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11.
A series of donor-stabilized N-silylphosphoranimine salts [DMAP.PCl2=NSiMe3]+X- (DMAP = 4-(dimethylamino)pyridine) were prepared by the reaction of Cl3P=NSiMe3 with DMAP in the presence of silver salts AgX (X = OSO2CF3, BF4, and SbF6). Repeating the reaction in the absence of AgX gave the chloride salt [DMAP.PCl2=NSiMe3]Cl which has been shown to be in equilibrium with free DMAP and Cl3P=NSiMe3. Attempts to stabilize a N-silylphosphoranimine cation with phosphine donors led to unexpected imine transfer chemistry. For example, Cl3P=NSiMe3 reacts with phosphines, R3P (R = nBu and Ph), to produce the metathesis products PCl3 and R3P=NSiMe3 which subsequently react together to afford the N-phosphinophosphoranimines R3P=N-PCl2 and ClSiMe3 as a byproduct. 相似文献
12.
Jaska CA Dorn H Lough AJ Manners I 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(1):271-281
Reaction of [Pt(PEt(3))(3)] with the primary and secondary phosphine-borane adducts PhRPH x BH(3) (R=H, Ph) resulted in oxidative addition of a P-H bond at the Pt(0) center to afford the complexes trans-[PtH(PPhR x BH(3))(PEt(3))(2)] (1: R=H; 2: R=Ph). The products 1 and 2 were characterized by (1)H, (11)B, (13)C, (31)P, and (195)Pt NMR spectroscopy, and the molecular structures were verified by X-ray crystallography. In both cases, a trans arrangement of the hydride ligand with respect to the phosphidoborane ligand was observed. When 2 was treated with PhPH(2) x BH(3), a novel phosphidoborane ligand-exchange reaction occurred which yielded 1 and Ph(2)PH x BH(3). Treatment of 2 with one equivalent of depe (depe=1,2-bis(diethylphosphino)ethane) resulted in the formation of the complex cis-[PtH(PPh(2) x BH(3))(depe)] (3), in which the hydride ligand and the phosphidoborane ligand are in a cis arrangement. Treatment of 3 with PhPH(2) x BH(3) was found to result in an exchange of the phosphidoborane ligands to give the complex cis-[PtH(PPhH x BH(3))(depe)] (4) and Ph(2)PH x BH(3). Complex 4 was found to undergo further reaction in the presence of PhPH(2) x BH(3) to give meso-cis-[Pt(PPhH x BH(3))(2)(depe)] (5) and rac-cis-[Pt(PPhH x BH(3))(2)(depe)] (6). 相似文献
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Choudhury M. Zakaria George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):m1-m4
In the adduct ferrocene‐1,1′‐diylbis(diphenylmethanol)–1,2‐bis(4‐pyridyl)ethene (1/1), [Fe(C18H15O)2]·C12H10N2, there is an intramolecular O—H?O hydrogen bond in the ferrocenediol component and a single O—H?N hydrogen bond linking the diol to the diamine, which is disordered over two sets of sites, so forming a finite monomeric adduct. In the adduct ferrocene‐1,1′‐diylbis(diphenylmethanol)–1,6‐diaminohexane (2/1), 2[Fe(C18H15O)2]·C6H16N2, the amine lies across a centre of inversion in space group P. There is an intramolecular O—H?O hydrogen bond in the ferrocenediol, and the molecular components are linked by O—H?N and N—H?O hydrogen bonds, one of each type, into a C(13)[R(12)] chain of rings. 相似文献
15.
Choudhury M. Zakaria George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):o204-o208
The adduct 1,6‐diaminohexane–1,1,1‐tris(4‐hydroxyphenyl)ethane (1/2) is a salt {hexane‐1,6‐diyldiammonium–4‐[1,1‐bis(4‐hydroxyphenyl)ethyl]phenolate (1/2)}, C6H18N22+·2C20H17O3?, in which the cation lies across a centre of inversion in space group P. The anions are linked by two short O—H?O hydrogen bonds [H?O 1.74 and 1.76 Å, O?O 2.5702 (12) and 2.5855 (12) Å, and O—H?O 168 and 169°] into a chain containing two types of R(24) ring. Each cation is linked to four different anion chains by three N—H?O hydrogen bonds [H?O 1.76–2.06 Å, N?O 2.6749 (14)–2.9159 (14) Å and N—H?O 156–172°]. In the adduct 2,2′‐bipyridyl–1,1,1‐tris(4‐hydroxyphenyl)ethane (1/2), C10H8N2·2C20H18O3, the neutral diamine lies across a centre of inversion in space group P21/n. The tris(phenol) molecules are linked by two O—H?O hydrogen bonds [H?O both 1.90 Å, O?O 2.7303 (14) and 2.7415 (15) Å, and O—H?O 173 and 176°] into sheets built from R(38) rings. Pairs of tris(phenol) sheets are linked via the diamine by means of a single O—H?N hydrogen bond [H?N 1.97 Å, O?N 2.7833 (16) Å and O—H?N 163°]. 相似文献
16.
Eric Rivard Andrew R. McWilliams Alan J. Lough Ian Manners 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4-5):845-847
An unusual, reversible skeletal substitution reaction involving boron- and aluminum-based heterophosphazenes is described. 相似文献
17.
Alan Lough 《合成通讯》2013,43(22):3387-3391
The bromoiodopropenoic acids (E)‐2‐bromo‐3‐iodopropenoic acid 5 and (Z)‐2‐bromo‐3‐iodopropenoic acid 6 were prepared by stereospecific nucleophilic substitution of the corresponding vinylic bromides. The structure of the (Z)‐isomer was confirmed by X‐ray crystallography. 相似文献
18.
[(IPent)PdCl2(morpholine)]: A Readily Activated Precatalyst for Room‐Temperature,Additive‐Free Carbon–Sulfur Coupling 下载免费PDF全文
Jennifer L. Farmer Matthew Pompeo Dr. Alan J. Lough Prof. Michael G. Organ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(48):15790-15798
A series of new, easily activated NHC–PdII precatalysts featuring a trans‐oriented morpholine ligand were prepared and evaluated for activity in carbon‐sulfur cross‐coupling chemistry. [(IPent)PdCl2(morpholine)] (IPent=1,3‐bis(2,6‐di(3‐pentyl)phenyl)imidazol‐2‐ylidene) was identified as the most active precatalyst and was shown to effectively couple a wide variety of deactivated aryl halides with both aryl and alkyl thiols at or near ambient temperature, without the need for additives, external activators, or pre‐activation steps. Mechanistic studies revealed that, in contrast to other common NHC–PdII precatalysts, these complexes are rapidly reduced to the active NHC–Pd0 species at ambient temperature in the presence of KOtBu, thus avoiding the formation of deleterious off‐cycle PdII–thiolate resting states. 相似文献
19.
20.
The stable monodentate Lindskog type bicarbonate nickel(ii) complex and its isomer have been prepared and fully characterized. 相似文献