I-butyraldehyde

By analogy between the oxo forms of vanadium(V) and iron(IV), the latter being the active species in oxidations by cytochrome P-450, the system constituted by vanadium oxide as the catalyst, and t-butylhydro-peroxide, as the oxidant, gives good results in the conversion of olefins to the corresponding epoxides. With the supported "clayniac" catalyst, in the presence of i-butyraldehyde as a sacrificial reducer, olefins are epoxidized in good yields by compressed air at room temperature, in a convenient procedure. 

This methodology, while commendable for its simplicity, has some drawbacks yields are not quantitative one has to invest i-butyraldehyde as a sacrificial reducer the resulting i-butyric acid has to be separated from the epoxide product, which detracts from the usefulness of the methodology. Nevertheless, as also shown by others recently (57), the Mukaiyama procedure can be adapted to good use. 

Figure 5. Complexes derived in 1% aldehyde solutions (a) from (Ph tj fRh(CO)H, (b)from AcacRh(CO)2plus 3TPP, and (c)from AcacRh(CO)23TPPunder 2 atm. H2 as shown in 1% i-butyraldehyde solution by 31P NMR at -60° C.

The copolymerisation of dimethylketene and acetaldehyde with diethylzinc as a catalyst produced a crystalline copolymer of alternating comonomer distribution (Table 9.3) [289], Other aldehydes such as w-butyraldehyde, i-butyraldehyde or benzaldehyde were also copolymerised with dimethylketene to produce the respective polyesters [289-318]. 

Pentafluoropropionaldehyde and heptafluoro-/i-butyraldehyde photochemically decompose by similar mechanisms. Absorption spectra due to CCl and CBr have been observed during the flash photolysis of chloral and bromal. 

The activation energy of this isomerization (38) would be regarded to be the same as that for (12). The formation of i-butyraldehyde as an important product requires not only the loss of a carbon atom from the structure, but also an internal H atom transfer from an adjacent carbon atom. Zeelenberg [181] and Fish [27] proposed a (1,4) methyl radical transfer,... 

Problem 32.14 When pbly(vinyl acetate) is treated with methanol (b.p. 65°) in the presence of a little sulfuric acid, a substance of b.p. 57° distills from the mixture, and a new polymer is left behind, (a) What reaction has taken place What is the structure of the new polymer Why must it be prepared in this indirect manner (b) When this new polymer is treated with i-butyraldehyde in the presence of a little phosphoric acid, a third polymer is formed, Butvar, which is used in making safety glass. What reaction has taken place here, and what is the structure of Butvar ... 

In what may be another example of true cluster catalysis, [HRu3(CO)i,] , shows catalytic activity for the hydroformylation of ethylene and propylene ". Solvent, CO partial P, and T are important variables. In monoglyme, at 80°C, and starting partial of CjHg, CO and Hj of 0.034, 0.022 and 0.011 MPa, respectively, the catalyst turnover number (mols product/mols catalyst) was 34.3 and the n- to i-butyraldehyde ratio was 49.4/1. In acetonitrile solvent, all other things being equal, the turnover number dropped to 25.7 and the isomer ratio decreased to 12.1/1. 

FIGURE 9.7 Aldehyde resin. Condensate of urea, formaldehyde and i-butyraldehyde, indicative structure (e.g. Laropal A 81). 

Urea/aldehyde resins (Figures 9.7 and A3.23) (de la Rie et al., 2002) are made by condensing urea, formaldehyde and i-butyraldehyde. These resins wet pigment particles well because of their polar groups. 

For PP acetone > acetaldehyde > methylacrolein> methyl ethyl ketone -I- butyraldehyde > methyl propyl ketone. 

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