Alcohol groups functionalization with

The biocatalytic reduction of the keto group to the alcohol group proceeds with a great tolerance of other functional groups in the substrate, for example, the enantioselective reductions of ketoesters to chiral hydroxyesters [70-73] or of... 

The oxidation of higher alkenes in organic solvents proceeds under almost neutral conditions, and hence many functional groups such as ester or lac-tone[26,56-59], sulfonate[60], aldehyde[61-63], acetal[60], MOM ether[64], car-bobenzoxy[65], /-allylic alcohol[66], bromide[67,68], tertiary amine[69], and phenylselenide[70] can be tolerated. Partial hydrolysis of THP ether[71] and silyl ethers under certain conditions was reported. Alcohols are oxidized with Pd(II)[72-74] but the oxidation is slower than the oxidation of terminal alkenes and gives no problem when alcohols are used as solvents[75,76]. 

The alcohol groups of carbohydrates undergo chemical reactions typical of hydroxyl functions They are converted to esters by reaction with acyl chlorides and carboxylic acid anhydrides... 

From this discussion, the limitations of the force field should have become clear. There is no such thing as a universal force field which describes every system in every condition. The force field is a function with few adjustable parameters and can, therefore, not be expected to reproduce all properties of all chemical species under all circumstances. This means, for example, that an OH group in an aliphatic alcohol will have to be treated differently from a phenolic OH or from the OH of a carboxylic acid group. Similarly, the density and temperature window of a force field is often limited [22]. 

Acetals are useful because they can act as protecting groups for aldehydes and ketones in the same way that trimethylsilyl ethers act as protecting groups for alcohols (Section 17.8). As we saw previously, it sometimes happens that one functional group interferes with intended chemistry elsewhere... 

With a secure route to pentacyclic amine 2, the completion of the total synthesis of 1 requires only a few functional group manipulations. When a solution of 2 in ethanol is exposed to Pd-C in an atmosphere of hydrogen, the isopropenyl double bond is saturated. When a small quantity of HCI is added to this mixture, the hydro-genolysis of the benzyl ether is accelerated dramatically, giving alcohol 15 in a yield of 96%. Oxidation of the primary alcohol in 15 with an excess of Jones reagent, followed by Fischer esterification, gives ( )-methyl homosecodaphniphyllate [( )-1] in an overall yield of 85 % from 2. 

In another interesting application of this procedure, the acid-mediated cascade cyclization of (3-diketone diepoxide 73 involves the participation not only of the two oxirane rings and of the secondary alcoholic group, but also of one of the two carbonyl groups. In this way, besides the two adjacent C and D THF rings, the simultaneous construction of the spiroketal function between the B and C rings of etheromycin is obtained (compound 74, in a 70 30 mixture with 12 -epi compound Scheme 8.19) [37]. 

The second compound above raises an important issue how do you name the functional group when you have two functional groups in a compound One will go in the suffix of the name and the other will be a prefix in the substituent part of the name. But how do we choose which one goes as the suffix of the name There is a hierarchy that needs to be followed. The six groups shown above are listed according to their hierarchy, so a carboxylic acid takes precedence over an alcohol. A compound with both of these groups is named as a ketone and we put the term hydroxy in the substituent part of the name. 

The hydroxy groups in natural products like, for example, the macrolide antibiotics erythromycin, 1"1 and desmycosin, 2001 2011 as well as the 3-(hydroxymethyl)-2- or 3-cephems 2021 and derivatives of the amino sugar garamin 2031 have been converted into the carbamate function with CDI and amines. In the case of aminoglycoside antibiotics of the sisomicin series, thiocarbamates or dithiocarbamates have been prepared from alcohols or thiols using ImCSIm and amines.12041... 

Metallocene catalysis has been combined with ATRP for the synthesis of PE-fr-PMMA block copolymers [123]. PE end-functionalized with a primary hydroxyl group was prepared through the polymerization of ethylene in the presence of allyl alcohol and triethylaluminum using a zirconocene/MAO catalytic system. It has been proven that with this procedure the hydroxyl group can be selectively introduced into the PE chain end, due to the chain transfer by AlEt3, which occurs predominantly at the dormant end-... 

The range of functional groups compatible with the molybdenum initiators includes fluoroalk-yls, esters, acetals and maleimides.531,532 However, protic functionalities such as alcohols and acids are not tolerated, and aldehydes terminate the polymerization. 

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