Rhenium bromide

Rhenium, tris(dithiodibenzoyl)-structure, 1, 63 Rhenium bromide Re3Br9... 

Rhenium, iris(cis-l, 2-diphenylethylene-l, 2-dithiolato)-structure, 24 Rhenium bromide RcjBr,... 

The performance of the Mamyrin instrument can be appreciated from the mass spectrum of the isotopic cluster of rhenium bromide trimer ions shown in Figure 3.2, in which mass resolution exceeds 1 part in 3000. 

FIGURE 3.2 (a) Oscillographic trace and (b) stroboscopic (boxcar) recording of a portion of the mass spectrum of rhenium bromide showing the isotopic ciuster from the trimer. (Reprinted with permission from reference 8). 

X-ray diffraction, which showed that the structure of the [Tc2Cl8]2 ions is analogous to that of the isoelectronic cluster rhenium and molybdenum chlorides and bromides with a quadruple M-M bond [1,89,90] (Fig. la, Table 1). 

Trirhenium nonabromide has been made (1) by direct combination of the elements 1 (2) by the thermal decomposition of rhenium (V) bromide, obtained by treating elemental rhenium with bromine at 650° 2 or (3) by the thermal decomposition of silver hexabromorhenate(IV),3-6 obtained from the metathesis of silver nitrate with potassium hexabromorhenate(IV).5-8 Of these methods, (3) has proven to be the simplest and most efficient route to pure trirhenium nonabromide. The following procedure is superior to that previously given,6 in that simpler equipment is used and larger quantities can be processed, with a resultant saving in time. 

The tube is positioned in a tube furnace so that the boat is near the center of the furnace, a thermocouple is introduced in the open end, and the open end of the furnace is plugged with Pyrex wool. The tube is evacuated and the temperature raised to 450° at about 3° per minute. A transitory blue deposit is formed in the cool portion of the tube at 200° at 300°, a green ring forms in the tube just inside the furnace at 300 to 350°, a blue-black deposit, presumably a mixture of rhenium (V) bromide and rhenium (VI) oxide tetrabromide,2 forms in the portion of the tube just outside the furnace at 350 to 370°, a blue-black... 

Rhenium (III) bromide is, as expected, more easily ionized, so that in DMSO the bisarsenate complex Re3Br3(AS04)2(DMS0)3 is readily produced 48). 

Other elements often separated from pile or cyclotron targets by distillation or volatilisation are tritium (3), germanium as the bromide (23), arsenic as the trichloride (67), technetium (23), (91), rhenium (24), (25) and osmium (25) as oxides. 

Narasaka and coworkers reported radical-polar crossover addition/cyclization reactions of phenacyl bromides 204 and electron-rich alkenes such as (silyl) enol ethers 205, catalyzed by the rhenium(I) complex 206 (Fig. 57) [302], The active catalyst 206A formed after thermal nitrogen elimination from 206 reduced 204 either directly or by oxidative addition/homolysis via rhenium enolate 204A to... 

The six-coordinate Re(C0)3(bipy)0C103 and Re(C0)50C103 are probably the only perchlorate complexes that are known for rhenium. They are prepared by treating the respective bromides with AgC104 in di-chloromethane (54). 

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