Phosphines carbonyl selenides

Several of the procedures discussed in the sulfoxide section describe the successful extension of the method to the reduction of selenoxides, - - and there is little doubt that many of the other procedures cited earlier could be used likewise. Sakaki and Oae used triphenylphosphine selenide and similar se-lenides to reduce selenoxides to selenides in 79-93% yield (equation 19). Using a chiral phosphine selenide, these workers showed that the phosphine oxide formed had suffered predominant inversion, with a stereospecificity of over 80%. Detty has reported the application of the silane PhSeSiMes (12) to the reduction of selenoxides and telluroxides. The reactions are rapid and proceed essentially quantitatively, even in the presence of a hydroxy or carbonyl group. 

Dimethyl sulfoxide (DMSO), (CH3)2SO, is a versatile reagent for the oxidation of alcohols to carbonyl compounds under gentle conditions. In addition to the previously mentioned dehydrogenations, it is capable of other oxidations acetylenes to a-diketones [997], alkyl halides to aldehydes 998, 999], tosyl esters to aldehydes [1000], methylene groups adjacent to carbonyl groups to carbonyls [1001, 1002], a-halocarbonyl compounds to u-dicarbonyl compounds [1003,1004,1005], aldehydes to acids [1006], and phosphine sulfides and selenides to phosphine oxides [1007]. 

Selenido-Carbonyl Clusters Derived from Phosphine and Diphosphine Selenides... 

In particular, the reaction of tertiary phosphine selenides with metal carbonyl complexes " provided a simple, one-step synthetic procedure for the formation of selenido clusters through oxidative transfer of selenium atoms to low-valent metal centers, taking advantage of the reactivity of the P=Se bond. 

Despite the synthetic potential of the phosphine selenides, their reactions with metal carbonyls have been explored only to a limited extent until the last three years, and most of the previously described chalcogenido-carbonyl clusters containing Group 15 donor ligands had been obtained by substitution reactions. ... 

Ozonation of Heteroatoms. Phosphines are converted to phosphine oxides and phosphites to phosphates by ozone. These reactions are quite general and a wide range of sub-stitutents can be tolerated. Phosphine oxides also can be produced by the ozonation of alkylidenetriphenylphosphoranes or of thio- or selenophosphoranes. Organic sulfides are converted to sulfoxides and sulfones by ozonation. Tertiary amines are converted to amine oxides, while nitro compounds can be produced in modest yields by ozonation of primary amines. This preparation of nitroalkanes compares well with alternate approaches using peroxides, peroxy acids, permanganate, or Monoperoxysulfuric Acid, but ozonation on silica gel has proven to be superior (see Ozone-Silica Get). Selenides are converted to selenoxides by ozone and this reaction is often used to achieve overall production of unsaturated carbonyl compounds. An example is shown in eq 25. ... 

Alkylperoxybenziodoxoles (Section 2.1.8.1.4) are useful oxidizing reagents toward organic sulfides, selenides and phosphines [527-529], Sulfides 426 can be oxidized with peroxybenziodoxole 427 under mild conditions to afford sulfoxides 428 in high yields (Scheme 3.172) [511], A similar oxidation of dithioac-etals 429 leads to regeneration of the parent carbonyl compound 430 and thus can be useful as a method for selective deprotection [511],... 

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