36219-40-6Relevant academic research and scientific papers
A 4 - bromo -3 - methyl -2 - butene -1 - ethoxylate ester preparation method (by machine translation)
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Paragraph 0023-0025, (2019/10/01)
The invention discloses a 4 - bromo - 3 - methyl - 2 - butene - 1 - ethoxylate ester preparation method, comprises the following steps: the isoprene and water is continuously pumped into the filled with bromo succinimide of the 1st [...] reaction is performed in a reactor, by the 1st rectifying device to obtain the rectification product 4 - bromo - 3 - methyl - 2 - butene - 1 - ol and 1 - bromo - 2 - methyl - 3 - butene - 2 - ol; the rectification product and of acetic anhydride mixture is pumped into the filled with solid acid catalyst in the reactor 2nd esterification rearrangement reaction, to obtain a reaction solution; the reaction liquid is distilled under reduced pressure to recover the acetic acid and unreacted second grade acid anhydride, 2nd rectifying device obtained by 4 - bromo - 3 - methyl - 2 - butene - 1 - ethoxylate ester. The invention of 4 - bromo - 3 - methyl - 2 - butene - 1 - ethoxylate ester preparation method the product yield is high, it is easy to realize continuous, large-scale production. (by machine translation)
Fast Assembly and High-Throughput Screening of Structure and Antioxidant Relationship of Carotenoids
Kim, Dahye,Shi, Gaosheng,Kim, Yunji,Koo, Sangho
supporting information, p. 714 - 718 (2019/01/25)
C20 heptaenyl diphosphonate 4 was prepared for one-pot synthesis of carotenoids 1. Olefination with various aromatic aldehydes allowed fast assembly of the corresponding carotenoids. The SAR of carotenoids was investigated by high-throughput screening of ABTS and DPPH assays and their hierarchical clustering analysis. Antioxidant activity of carotenoids increased with the number of electron-donating substituents. Carotene 1a with multiple electron-donating substituents was most proficient, which showed better radical scavenging activities than β-carotene and lycopene.
Amino-functionalized (meth)acryl polymers by use of a solvent-polarity sensitive protecting group (Br-t-BOC)
Ritter, Helmut,Tabatabai, Monir,Herrmann, Markus
, p. 245 - 252 (2016/04/05)
We describe the synthesis of bromo-tert-butyloxycarbonyl (Br-t-BOC)-amino-protected monomers 2-((1-bromo-2-methylpropan-2-yl)oxycarbonylamino)ethyl (meth)acrylate 3a,b. For this purpose, 2-isocyanatoethyl (meth)acrylate 1a,b was reacted with 1-bromo-2-methylpropan-2-ol (2a). The free radical polymerization of (Br-t-BOC)-aminoethyl (meth)acrylates 3a,b yielded poly((Br-t-BOC)-aminoethyl (meth)acrylate) 6a,b bearing protected amino side groups. The subsequent solvolysis of the Br-t-BOC function led to the new polymers poly(2-aminoethyl (meth)acrylate) 8a,b with protonated free amino groups. The monomers and the resulting polymers were thoroughly characterized by 1H NMR, IR, GPC and DSC methods. The kinetics of the deprotection step was followed by 1H NMR spectroscopy. The solvent polarity and neighboring group effects on the kinetics of deprotection are discussed.
Efficient syntheses of climate relevant isoprene nitrates and (1R,5S)-(-)-myrtenol nitrate
Bew, Sean P.,Hiatt-Gipson, Glyn D.,Mills, Graham P.,Reeves, Claire E.
, p. 1081 - 1095 (2016/07/06)
Here we report the chemoselective synthesis of several important, climate relevant isoprene nitrates using silver nitrate to mediate a 'halide for nitrate' substitution. Employing readily available starting materials, reagents and Horner-Wadsworth-Emmons chemistry the synthesis of easily separable, synthetically versatile 'key building blocks' (E)- and (Z)-3-methyl-4-chlorobut-2-en-1-ol as well as (E)- and (Z)-1-((2-methyl-4-bromobut-2-enyloxy)methyl)-4-methoxybenzene has been achieved using cheap, 'off the shelf' materials. Exploiting their reactivity we have studied their ability to undergo an 'allylic halide for allylic nitrate' substitution reaction which we demonstrate generates (E)- and (Z)-3-methyl-4-hydroxybut-2-enyl nitrate, and (E)- and (Z)-2-methyl-4-hydroxybut-2-enyl nitrates ('isoprene nitrates') in 66-80% overall yields. Using NOESY experiments the elucidation of the carbon-carbon double bond configuration within the purified isoprene nitrates has been established. Further exemplifying our 'halide for nitrate' substitution chemistry we outline the straightforward transformation of (1R,2S)-(-)-myrtenol bromide into the previously unknown monoterpene nitrate (1R,2S)-(-)-myrtenol nitrate.
C5 BENZOTHIAZOLYL SULFONE COMPOUND, METHOD OF PREPARING THE SAME, METHOD OF PREPARING POLYENE DIALDEHYDE COMPOUND USING THE SAME, AND METHOD OF SYNTHESIZING LYCOPENE USING THE SAME
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Paragraph 0037, (2016/03/04)
Disclosed are a novel C5 benzothiazolyl sulfone compound having an acetal protecting group, a method of preparing the same, and a method of efficiently preparing an apo-carotene dialdehyde compound having a polyene dialdehyde structure using the same. Also, a method of efficiently preparing lycopene by olefination (Julia-Kocienski) between the apo-carotene dialdehyde compound (C20 crocetin dialdehyde) and C10 benzothiazolyl geranyl sulfone is provided.
PREPARATIVE SYNTHESIS OF ISOPRENE OXIDE
Arakelyan, A. S.,Dvoryanchikov, A. I.,Gevorkyan, A. A.
, p. 604 - 605 (2007/10/02)
The reaction of isoprene, hydrogen peroxide, and commercial hydrobromic acid gives 1-bromo-2-methyl-3-buten-2-ol, the low-temperature dehydrobromination of which gives isoprene oxide in high yield.
Transition-metal-catalyzed Grignard Reaction of Isoprene Bromohydrin
Araki, Shuki,Ohmura, Masayuki,Butsugan, Yasuo
, p. 1607 - 1608 (2007/10/02)
The coupling reaction of isoprene bromohydrin with aryl and alkyl Grignard reagents catalyzed by tetrakis(triphenylphosphine)palladium(0) selectively gave the vinyl-group-migrated products.
CARBON-CARBON BOND FORMATION UNDER MILD CONDITIONS VIA TANDEM CATIONIC AZA-COPE REARRANGEMENT-MANNICH REACTIONS. A CONVENIENT SYNTHESIS OF POLYSUBSTITUTED PYRROLIDINES.
Overman,Kakimoto,Okazaki,Meier G. Patrick
, p. 6622 - 6629 (2007/10/02)
The reaction of aldehydes (or ketones) with 2-alkoxy(or hydroxy)-3-alkenamines achieves a general and high-yielding synthesis of polysubstituted 3-acylpyrrolidines (eq 5-9). This tandem cationic aza-Cope rearrangement-Mannich cyclization reaction (eq 1) o
