Phosphorus trichloride stereochemistry

Brown and co-workers synthesized optically active phosphine oxides from phosphorus trichloride by sequential addition of nucleophiles to chiral oxazaphospholidine [Eq. (24)]. The key step in this synthesis is control of the stereochemistry of the oxazaphospholidine, since the stereochemistry from the other steps is well characterized. The overall result is a greater than 94% e.e. 

A number of new sources of the known aspidospermidine derivatives (24-50) have been revealed in recent years 5,6,9,10,13,38,54-65,71,74-78) and are listed in Table 1. Fourteen new alkaloids have been isolated including (-i-)-l,2-didehydroaspidospermidine N-oxide (51), which is a constituent of the roots of R. stricta 66). Its structure was deduced from its spectroscopic properties, but an attempt to assign the absolute stereochemistry by removal of the A-oxide function by reduction or reaction with phosphorus trichloride met with failure, the product obtained being an unidentified indole derivative. 

The bicyclic compound (14) formed by the reaction of phosphorus trichloride with an amino-diketone <84JA1164> has been shown to be planar, which has been interpreted as evidence for the delocalized dipolar canonical structure (15) rather than the neutral form (14). It forms a silver complex with trigonal bipyramidal stereochemistry at phosphorus <91JA1071>. 

Phosphorus tribromide stereochemistry, 36 Phosphorus trichloride metal complexes solvolysis, 418 stereochemistry, 36 Phosphorus trifluoride stereochemistry, 36 Phosphorus trihalides stereochemistry, 36 Phosphorus triiodidc stereochemistry, 36 Photoaquation solid state, 471 Photocalorimetry, 410 Photochemical reactions, 397 applications, 408 mechanisms, 385 solid state, 470 Photochromism, 409 Photolysis... 

The crystalline addition complex formed between phosphorus trichloride and tetraethylammo-nium chloride is quite unusual, and is correctly formulated as Et4N+ PCI4 [42], Unlike the tetrahedral PCI4 cation, the PCI4 anion adopts a distorted trigonal bipyramidal configuration in which one equatorial arm is believed to be occupied by a lone pair of electrons (4.298). In this instance, there is a resemblance to the stereochemistry of arsenic and antimony (Chapter 3.2). 

N.Q.R. The C1 n.q.r. spectra of cyclic 1,3,2-/i -diazaphosphorines correlate with parameters estimated by CNDO/2 calculations. The structures of the intermediates produced in the reactions of formamides and acetamides with phosphorus pentachloride and phosphoryl trichloride have been studied by n.q.r. spectroscopy. The stereochemistry of dichlorodiazadiphosphetane has been studied, and evidence on the polarity of radial chloride atoms in chlorophosphoranes discussed. ... 

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