Starters aldehydes

Surprisingly the water consumption of a starter battery, provided it contains anti-monial alloys, is affected by the separator. Some cellulosic separators as well as specially developed polyethylene separators (e.g., DARAMIC V [76]) are able to decrease the water consumption significantly. The electrochemical processes involved are rather complex and a detailed description is beyond the scope of this chapter. Briefly, the basic principle behind the reduction of water loss by separators is their continuous release of specific organic molecules, e.g., aromatic aldehydes, which... 

The other acetogenins, shown in Table II, are a varied assortment of small molecule compounds which as a group contain alkene, alcohol, and carbonyl (acid, ester, aldehyde, and ketone) functionality. They are fairly typical substances with common structural features. Again, those compounds possessing an odd number of carbon atoms are less common, and biogenetlcally may be derived from a propionate starter unit. 

Butter Starter Distillate, 394 Butyl Acetate, 462, 649 -Butyl Acetate, 462 Butyl Alcohol, 462, 649, (S 1)62 Butyl Aldehyde, 462 Butylated Hydroxyanisole, 44 Butylated Hydroxymethylphenol, 51 Butylated Hydroxytoluene, 45 Butyl Butyrate, 462, 650 n-Butyl -Butyrate, 462 Butyl Butyryllactate, 462, 609 2-sec-Butyl Cyclohexanone, (S3)66, 97... 

Figure 13.1 Starters with aromatic structure (condensates of phenols with aldehydes)...

The polyols for rigid foams (referred to as rigid polyols) discussed before (Chapters 13 and 14), are based on the alkoxylation of different polyols or polyamines, commercialised in a relatively high purity form. Some important starters for rigid polyols are obtained by the synthesis of the starter in situ, before the alkoxylation reaction, by the condensation reaction of some aromatic compounds (phenols, melamine and so on) with aldehydes (mainly formaldehyde), followed by the reaction of the resulting condensate with alkylene oxides. Some important rigid polyols based on the condensates mentioned are ... 

When studies of the subject were initiated, both the putative extended-chain elongation and the reduction steps were not known in nature, but the above is the situation as now perceived. Other mechanisms are possible thus various even and odd n-alkanes could be produced by modification of aldehydes formed by cleavage of a double bond situated internally in a long-chain precursor odd-carbon fatty acids and thus smaller even-carbon n-alkanes could result from chain elongation using a propionate (C3) unit as a starter rather than acetate and n-fatty acids could be directly reduced to n-alkanes without loss of carbon via the intermediacy of aldehydes and alcohols. However, no evidence has been uncovered for any of these processes, although admittedly work in the field is not extensive. 

Kishimoto Y, Williams M, Moser H, Hignite C and Biemann K (1973) Branched-chain and odd-numbered acids and aldehydes in the nervous system of a patient with deranged vitamin Bn metabohsm. J Lipid Res 14 69 Klaenhammer TR (1988) Bacteriocins of lactic acid bacteria. Biochimie 70 337-349 Konoplev EG and Scherbakov LA (1970) Application of mixed starter cultures of... 

Sulfuryl chloride and a radical starter produce the same mixture [563-566]. The radical chlorination may be regulated by phosphorus oxychloride plus radical starter [567] or phosphorus trichloride plus radical starter [568]. But just radical starter in carbon tetrachloride [569] does the same. Apparently the purity of all compounds involved plays a major role. Pure monochloride 276 can be obtained by partial photo chlorination in the gas-/liquid-phase at 270 °C [570, 571]. For the mono-bromination under irradiation in carbon tetrachloride special measures must be taken [573, 574], however these are seldom ensured under normal conditions. Usually, in that case one has to accept the mixture of mono- and dibromide 277, 278 for conversion to the aldehyde. Dibromo tetrachloroethane was recommended for bromination at 150 °C without bromination of the aromatic nucleus. Bromination at 270 °C yields the same mixture [563]. Larger amounts of radical starters and pure 3-phenoxytoluene... 

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