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This structure is typical for four-coordinate 18 e − complexes. [2] The corresponding complexes Ni(PPh 3) 4 and Pt(PPh 3) 4 are also well known. Such complexes reversibly dissociate PPh 3 ligands in solution, so reactions attributed to Pd(PPh 3) 4 often in fact arise from Pd(PPh 3) 3 or even Pd(PPh 3) 2. [3]
Portopulmonary hypertension (PPH) [1] is defined by the coexistence of portal and pulmonary hypertension. PPH is a serious complication of liver disease, present in 0.25 to 4% of all patients with cirrhosis. Once an absolute contraindication to liver transplantation, it is no longer, thanks to rapid advances in the treatment of this condition. [2]
In the first step, PtCl 2 (PPh 3) 2 is generated. In the second step, this platinum(II) complex is reduced. The overall synthesis can be summarized as: K 2 [PtCl 4] + 2KOH + 4PPh 3 + C 2 H 5 OH → Pt(PPh 3) 4 + 4KCl + CH 3 CHO + 2H 2 O. Pt(PPh 3) 4 reacts with oxidants to give platinum(II) derivatives: Pt(PPh 3) 4 + Cl 2 → cis-PtCl 2 (PPh 3 ...
In the Appel reaction, a mixture of PPh 3 and CX 4 (X = Cl, Br) is used to convert alcohols to alkyl halides. Triphenylphosphine oxide (OPPh 3) is a byproduct. PPh 3 + CBr 4 + RCH 2 OH → OPPh 3 + RCH 2 Br + HCBr 3. This reaction commences with nucleophilic attack of PPh 3 on CBr 4, an extension of the quaternization reaction listed above.
Several crystal structures containing PdCl 2 (PPh 3) 2 have been reported. In all of the structures, PdCl 2 (PPh 3) 2 adopts a square planar coordination geometry and the trans isomeric form. [5] [6] [7] [8]
The rate is higher for multiple pregnancies (32.4% compared with 10.6% for singletons), and for first-time mothers (12.9% compared with 10.0% for women in subsequent pregnancies). [56] The overall rate of severe PPH (>1000 ml) was much lower at an overall rate of 2.8%, again with the highest rate in Africa (5.1%). [56]
A Patent Cooperation Treaty/Patent Prosecution Highway (PCT/PPH) pilot program was also started on 29 January 2010 for a planned period of two years. This pilot program enables to "[fast-track] patent examination procedures for PCT applications that have received a positive written opinion of either the International Searching Authority or the International Preliminary Examining Authority, or ...
Pound per hour is a mass flow unit based on the international avoirdupois pound, which is used in both the British imperial and, being a former colony of Britain, the United States customary systems of measurement.