Bismuth formate complexes, preparation

The Reppe process is a method that was developed in the 1940s and typical manufacturers include BASF, Ashland, and Invista. Cu-Bi catalyst supported on silica is used to prepare the 1,4-butynediol by reacting formaldehyde and acetylene at 0.5 MPa and 90-110 C (Eq. (10.2)). The copper used in the reaction is converted to copper(I) acetylide, and the copper complex reacts with the additional acetylene to form the active catalyst. The role of bismuth is to inhibit the formation of water-soluble acetylene polymers (i.e., cuprenes) from the oligomeric acetylene complexes on the catalyst [5a]. The hydrogenation of 1,4-butynediol is accom-pUshed through the use of Raney Ni catalyst to produce 1,4-butanediol (Eq. (10.3)). The total yield of 1,4-butanediol production is 91% from acetylene [5b]. Since acetylene is a highly explosive compound, careful process control is necessary. 

Tl -bismolyl derivative [Mn(CO)jL] (81) (L=2,5-Me2C4H2Bi). Two papers describe the formation of triiron complexes [ Fe(CO)4 3(p -BiR)] in which bismuth is tetrahedral, addition of acetic acid to which affords rectangular complexes [Fc(CO)4(p-BiR)]2 . Another publication details the preparation of a whole range of complexes in which a bismuth nitrate unit is linked to two metal centres , while thermolysis of NaBi03 and [Mo(CO)J in methanol for a day, followed by addition of Et4NBr yields the unusual cluster [Mo3(CO)9(p -Bi) p -(OMej)Mo(CX))3 ][NEt4]2, which contains a naked bismuth atom (82) . ... 

The bismuth aUcoxide was insoluble in methoxyethanol because of its own strong association however, it easily dissolved in methoxyethanol containing strontium alkoxide in Sr(OR)2 Bi(OR)3 molar ratios of >0.5 (Katayama and Sekine, 1991). As previously reported, the strong association of the bismuth alkoxide can be destroyed by the formation of a strontium-bismuth double alkoxide. The formation of the strontium-bismuth double alkoxide is discussed next. Also, the bismuth alkoxide was insoluble in strontium-tantalum or strontium-niobium double alkoxide solutions. The strontium-bismuth double alkoxide formed and then reacted with the tantalum or niobium alkoxide to prepare uniform alkoxide complex solutions (Kato et al., 1998). 

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