29576-14-5

Usage

Uses

Used in Pharmaceutical Industry:
Crotyl bromide is used as a synthetic building block for the production of biologically important natural products and their derivatives. It plays a crucial role in the total synthesis of compounds such as (+)-artemisinin, plakortone E, and (?)-horsfiline, which have significant pharmaceutical applications.
Used in Chemical Synthesis:
Crotyl bromide is used as a general organic reagent for the preparation of various analogs, including deoxycyclitols, pentopyranoses, 6-deoxyhexoses, hexoses, and pseudo-indoxyl derivatives. These analogs are essential in the development of new chemical compounds and materials, contributing to advancements in various industries.

Purification Methods

Dry the bromide with MgSO4/CaCO3 mixture and fractionally distil it through an all-glass Todd column (p 11). [Beilstein 1 IV 789.]

InChI:InChI=1S/C4H7Br/c1-2-3-4-5/h2-3H,4H2,1H3/b3-2+

Upstream product

• 598-32-3 2-hydroxy-3-butene 
• 22037-73-6 3-bromo-1-butene 
• 590-18-1 (Z)-2-Butene 
• 18269-32-4 crotyl alcohol trimethylsilyl ether 
• 78-76-2 s-butyl bromide 
• 10035-10-6 hydrogen bromide 
• 64-19-7 acetic acid 
• 106-99-0 buta-1,3-diene 
• 110-86-1 pyridine 
• 7789-60-8 phosphorus tribromide 
• 2482-57-7 1-bromo-2-butanol 
• 6117-91-5 (E/Z)-2-buten-1-ol 
• 7664-93-9 sulfuric acid 
• 627-27-0 homoalylic alcohol 

Downstream Products

• 106-98-9 1-butylene 
• 107-01-7 butene-2 
• 1569-59-1 3-methylpent-4-en-2-ol 
• 101498-47-9 but-2ξ-enyl-(2,4-dimethyl-6-trans-propenyl-phenyl)-ether 
• 6443-92-1 (Z)-hept-2-ene 
• 14686-13-6 (E)-hept-2-ene 
• 18448-88-9 2-crotylphenol 
• 106-99-0 buta-1,3-diene 
• 91091-32-6 3,5-dinitro-benzoic acid-(buten-(2c)-yl ester) 
• 119558-86-0 but-2-enyl-phenyl-malonic acid diethyl ester 
• 1560-06-1 1-phenyl-2-butene 
• 504-61-0 (E)-but-2-enol 
• 598-32-3 2-hydroxy-3-butene 
• 6117-91-5 (E/Z)-2-buten-1-ol 

Relevant academic research and scientific papers

An acyl-Claisen/Paal-Knorr approach to fully substituted pyrroles

The synthesis of fully substituted pyrroles using the Paal-Knorr reaction on acyl-Claisen derived 2,3-syn-disubstituted-1,4-diketones is reported. The use of the acyl-Claisen rearrangement allows the synthesis of wide variety of syn-substituted 1,4-diketones which are shown to be better substrates for pyrrole condensation than their corresponding anti isomers. When the reaction was performed open to air the use of nucleophilic amines in the pyrrole forming step leads to auto-oxidation of the 5-methyl group giving exclusively 5-formyl pyrroles.

Local Conformer Effects in Unsaturated Lactones

Allylic unsaturated lactones 5E and 5Z can be epoxidized and osmylated with useful stereocontrol.The epoxidations follow the pattern predicted from evaluation of local conformer effects, and epoxides 8 and 14 are favored.These products correspond to peripheral attack on the exposed olefin face of conformers similar to 1 (Z-alkene) or 2 (E-alkene).As in the case of simple carbocyclic alkenes, osmylation of the Z-isomer (5Z) follows the same selectivity pattern as the epoxidation, and 16 is the major diol.However, the isomeric 5E is osmylated from the opposite olefin face compared to the epoxidation and gives 13 as the major diol.The analysis of epoxidations by the local conformer approach is compared with the results of molecular mechanics (MACROMODEL) evaluations of the favored conformers of 5E and 5Z and of the derived epoxides.

A mild method for the replacement of a hydroxyl group by halogen: 3. the dichotomous behavior of α-haloenamines towards allylic and propargylic alcohols

A study of the deoxyhalogenation of allylic and propargylic alcohols with tetramethyl-α-halo-enamines is reported. Primary allylic and primary and secondary propargylic alcohols gave the corresponding halides in high yields. Secondary allylic and propargylic alcohols yielded the corresponding secondary halides but the reaction also produced some rearranged primary halides (I > Br > Cl). The reactions with tertiary allylic and tertiary propargylic alcohols gave several products and was therefore of little synthetic value. However, the addition of triethylamine to the reaction mixture or the use of lithium alkoxide instead of alcohol brought about a major change of the course of the reaction which led to amides carrying an allyl or an allenyl group at C2. This was shown to result from a Claisen-Eschenmoser rearrangement of an intermediate α-allyloxy- or propargyloxy-enamine.

Alkyne Aminopalladation/Heck and Suzuki Cascades: An Approach to Tetrasubstituted Enamines

Alkyne aminopalladation reactions starting from tosylamides are reported. The emerging vinylic Pd species are converted either in an intramolecular Heck reaction with olefinic units or in an intermolecular Suzuki reaction by using boronic acids exhibiting broad functional group tolerance. Tetra(hetero)substituted tosylated enamines are obtained in a simple one-pot process.

Regiospecific Synthesis of Calcium-Independent Daptomycin Antibiotics using a Chemoenzymatic Method

Daptomycin (DAP) is a calcium (Ca2+)-dependent FDA-approved antibiotic drug for the treatment of Gram-positive infections. It possesses a complex pharmacophore hampering derivatization and/or synthesis of analogues. To mimic the Ca2+-binding effect, we used a chemoenzymatic approach to modify the tryptophan (Trp) residue of DAP and synthesize kinetically characterized and structurally elucidated regiospecific Trp-modified DAP analogues. We demonstrated that the modified DAPs are several times more active than the parent molecule against antibiotic-susceptible and antibiotic-resistant Gram-positive bacteria. Strikingly, and in contrast to the parent molecule, the DAP derivatives do not rely on calcium or any additional elements for activity.

Visible-Light-Promoted Intramolecular α-Allylation of Aldehydes in the Absence of Sacrificial Hydrogen Acceptors

We report herein an unprecedented protocol for radical cyclization of aldehydes with pendant alkenes via synergistic photoredox, cobaloxime, and amine catalysis. The transformation was achieved in the absence of external oxidants, providing a variety of 5-, 6-, and 7-membered ring products with alkene transposition in satisfactory yields. The reaction exhibits wide functional group compatibility and occurs under mild conditions with extrusion of H2.

Ruthenium-catalyzed enantioselective C-H functionalization: A practical access to optically active indoline derivatives

Ru(II)-catalyzed enantioselective C-H activation/hydroarylation has been developed for the first time, allowing for highly enantioselective synthesis of indoline derivatives via catalytic C-H activation. Commercially available Ru(II) arene complexes and chiral α-methylamines were employed as highly enantioselective catalysts. Based on a sterically rigidified chiral transient directing group, multisubstituted indolines were produced in up to 92% yield with 96% ee. Further transformation of the resulting 4-formylindoline enables access to an optically active tricyclic compound that is of potential biological and pharmaceutical interest.

ATF3 INDUCTION COMPOUNDS

Provided are compounds for treating and/or preventing obesity and obesity-related disorders. Particularly, provided are chromanone derivatives used as ATF3 inducer and for treating and/or preventing obesity and obesity-related disorders such as heart disease, hypertension, hyperlipidemia and diabetes.

Forging C-C Bonds with Hindered Nucleophiles and Carbonyl Electrophiles: Reactivity and Selectivity of Allylic Tin Reagents/n-BuLi

Under activation with n-BuLi, trialkylstannanes containing crotyl-, geranyl-, and phenyldienylmethyl appendages were reacted with efficiency and selectivity to various ketone and enone electrophiles with low reactivity. The straightforward process gives access to tertiary alcohols that are vicinal to quaternary carbons. With α,α′-dimethoxy-γ-pyrone, on the other hand, the grafting of a dienyl side chain was effected to prepare dienyl α′-methoxy-γ-pyrone in a stereo- and regioselective and convergent manner. Furthermore, the advantages of this route were highlighted for the preparation of organolithium species at low temperature with the formation of a minimum amount of salts. Synthetic manipulations were demonstrated to illustrate the potential of the chemistry for constructing acyclic and cyclic terpene scaffolds.

A mild method for the replacement of a hydroxyl group by halogen. 1. Scope and chemoselectivity

α-Chloro-, bromo- and iodoenamines, which are readily prepared from the corresponding isobutyramides have been found to be excellent reagents for the transformation of a wide variety of alcohols or carboxylic acids into the corresponding halides. Yields are high and conditions are very mild thus allowing for the presence of sensitive functional groups. The reagents can be easily tuned allowing therefore the selective monohalogenation of polyhydroxylated molecules. The scope and chemoselectivity of the reactions have been studied and reaction mechanisms have been proposed.