Table of Contents
How is tetrahydropyran formed?
The reaction of tertiary 1,4- and 1,5-diols with cerium ammonium nitrate at room temperature gives tetrahydrofuran and tetrahydropyran derivatives in high yield and stereoselectivity. Various fragrant compounds have been synthesized using this method.
What is tetrahydropyran used for?
2-Tetrahydropyranyl (THP-) ethers derived from the reaction of alcohols and 3,4-dihydropyran are commonly used as protecting groups in organic synthesis. Furthermore, a tetrahydropyran ring system, i.e., five carbon atoms and an oxygen, is the core of pyranose sugars, such as glucose.
What is THP in organic chemistry?
Tetrahydropyran (THP): A saturated heterocyclic ring containing five sp3 carbon atoms and one sp3 oxygen atom having the molecular structure shown below, or a molecule containing this moiety. Most frequently encountered in pyranose carbohydrates, or as an alcohol protecting group.
Is tetrahydropyran polar?
Information on this page: Normal alkane RI, non-polar column, custom temperature program. References. Notes.
Is tetrahydropyran soluble in water?
|melting point (C)||-45 C||PhysProp|
|boiling point (C)||88 C||PhysProp|
|water solubility||8.02E+004 mg/L (at 25 C)||YALKOWSKY,SH & DANNENFELSER,RM (1992)|
|logP||0.95||HANSCH,C ET AL. (1995)|
What does THF stand for in chemistry?
|Chemical Safety||Laboratory Chemical Safety Summary (LCSS) Datasheet|
|Molecular Formula||C4H8O or (CH2)3CH2O|
|Synonyms||TETRAHYDROFURAN Oxolane 109-99-9 Furan, tetrahydro- Furanidine More…|
How do I get rid of THP?
To remove THP (protecting a primary -OH in a compound with an additional ester group) you can use Amberlyst -15 as a mild acid reagent.
What is THP protecting group?
The tetrahydropyranyl ether is a useful protecting group for the protection of alcohols and phenols, offering stability towards strongly basic reaction conditions, organometallics, hydrides, acylating reagents and alkylation reagents. … THP ethers are formed under acidic conditions from alcohols and dihydropyran.
Which of the following acts Umpolung reagent?
The canonical umpolung reagent is the cyanide ion.
Why is THP used as a protecting group?
It has several advantages, including low cost, ease of introduction, general stability to most nonacidic reagents, it confers good solubility, and the ease with which it can be removed if the functional group it protects requires manipulation. However, little attention has been paid to Thp in peptide chemistry.
What is THP medical?
THP ( docetaxel. Also called Taxotere. A medicine used together with other agents to treat certain types of breast cancer, stomach cancer, prostate cancer and certain types of head and neck cancer.
How do I remove SEM protecting groups?
SEM groups can be removed from protected heterocycles or nitrogen containing compounds using hydrochloric acid under refluxing conditions or at elevated temperature, while SEM protecting groups on nucleosides have been removed using tin tetrachloride at low temperature.
What is pyran ring?
In chemistry, pyran, or oxine, is a six-membered heterocyclic, non-aromatic ring, consisting of five carbon atoms and one oxygen atom and containing two double bonds. … The term pyran is also often applied to the saturated ring analog, which is more properly referred to as tetrahydropyran (oxane).
Is tetrahydrofuran soluble in water?
|Melting point||108.4 C (163.1 F; 164.8 K)|
|Boiling point||66 C (151 F; 339 K)|
|Solubility in water||Miscible|
|Vapor pressure||132 mmHg (20 C)|
Is ethyl acetate miscible in water?
Since ethyl acetate is incapable of effectively separating the Coulombic forces of attraction between the water molecules, these two liquids are immiscible.
Is dioxane soluble in water?
1,4-Dioxane is a synthetic industrial chemical that is completely miscible in water (EPA 2006; ATSDR 2012). Synonyms include dioxane, dioxan, p-dioxane, diethylene dioxide, diethylene oxide, diethylene ether and glycol ethylene ether (EPA 2006; ATSDR 2012; Mohr 2001).
Why is THF a solvent?
THF is also a popular solvent choice for small-scale laboratory experiments, mainly because it can dissolve a wide variety of organic compounds and has a relatively low boiling point. The low boiling point is convenient because it makes the solvent easy to remove from the chemical reaction by evaporation.
Why is THF hazardous?
* Breathing Tetrahydrofuran can irritate the nose, throat and lungs causing coughing, wheezing and/or shortness of breath. * Tetrahydrofuran can cause headache, nausea and dizziness. Very high exposure can cause unconsciousness and death. … * Tetrahydrofuran is a FLAMMABLE LIQUID and a DANGEROUS FIRE HAZARD.
What is the purpose of silyl ether?
Silyl ethers are usually used as protecting groups for alcohols in organic synthesis. Since R1R2R3 can be combinations of differing groups which can be varied in order to provide a number of silyl ethers, this group of chemical compounds provides a wide spectrum of selectivity for protecting group chemistry.
What is the use of FMOC protecting group in organic synthesis?
Protection of Amino Groups New, stable amino-protecting reagents, Boc-DMT and Fmoc-DMT, were prepared, and found to be useful for the introduction of Boc and Fmoc groups into amines. Both the reagents can protect various amines including amino acids in good yield in aqueous media.
Which Synthons is an example of umpolung?
Acyl anion equivalents, among the most common umpolung synthons, can be pro-duced by many strategies. For instance, nitroalkanes can be used as nucleophiles and the nitro function can be cleaved to the carbonyl group. Thus nitronates can be thought of as acyl anion equivalents.
What is umpolung explain with example?
The original meaning of the term has been extended to the reversal of any commonly accepted reactivity pattern. For example, reaction of R-C CX (X = halide) as a synthon for R-C C+ (i.e. electrophilic acetylene) is an umpolung of the normal more common acetylide, R-C. C- (i.e. nucleophilic) reactivity.
How are amines synthesized?
Nsubstituted amines are produced by reaction of ketones with primary amines, followed by reduction. N,Ndisubstituted amines can be produced by reaction of 2 amines with ketones followed by reduction.