Formaldehyde aliphatic diol reaction

The ease of acetal formation depends largely on the structures of the reacting carbonyl compounds and alcohol.905 Primary alcohols react better than secondary or tertiary ones the ease of reaction of carbonyl compounds decreases in the order formaldehyde, aliphatic aldehydes,, / -unsaturated aldehydes, aromatic aldehydes, ketones acetone gives cyclic ketals very readily with 1,2- and 1,3-diols. 

The synthesis of aliphatic polyformals (X) been known for many years and is relatively straightforward. As shown in equation 1, aliphatic diols can be reacted directly with formaldehyde or dialkyl formals to produce these polymers. The principal complication of the reaction occurs when the diol used contains 2, 3 or 4 carbon atoms in which case the formation of the cyclic formal is favored. Musser and Jackson have more... 

Biological systems overcome the inherent unreactive character of 02 by means of metalloproteins (enzymes) that activate dioxygen for selective reaction with organic substrates. For example, the cytochrome P-450 proteins (thiolated protoporphyrin IX catalytic centers) facihtate the epoxidation of alkenes, the demethylation of Al-methylamines (via formation of formaldehyde), the oxidative cleavage of a-diols to aldehydes and ketones, and the monooxygenation of aliphatic and aromatic hydrocarbons (RH) (equation 104). The methane monooxygenase proteins (MMO, dinuclear nonheme iron centers) catalyze similar oxygenation of saturated hydrocarbons (equation 105). ... 

Aliphatic alkenes also undergo the Prins reaction and a well-conducted example is with propene, formaldehyde and HC1. The product is 4-chloro-tetrahydropyran in good yield.32 This compound presumably arises from the cyclisation of another diol 194 and that clearly comes from one molecule of propene and two of formaldehyde. What is different from the last example is that the two molecules of formaldehyde must have been added to opposite ends of the original propene. 

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