Tag: M.W=200-250

Dubois, Jacques-Emile published the artcileReactivity of methyl-substituted ethylenebromonium ions. Correlation between charge distribution and regio- or chemoselectivity, Application of 2,3-Dibromo-2,3-dimethylbutane, the publication is Journal of the American Chemical Society (1978), 100(11), 3506-13, database is CAplus.

The opening of 7 Me-substituted bromonium ions by competitive nucleophilic attack with MeOH and Br^– in MeOH containing 0.2 M NaBr was studied. In each case the dibromoalkane and the bromomethoxyalkane (and its anti-Markovnikov isomer are formed. Chemoselectivity, expressed as % bromomethoxyalkane, varies from 38-84.7%, but does not vary linearly with the number of Me groups. This nonadditivity comes from the role played by Br in the charge distribution on C sites in the ethylenebromonium ion. This charge distribution is evaluated from Olah’s measurements of ¹³C NMR shifts of these ions stabilized in a superacid medium. Chemoselectivity correlates with the charge distribution on the C atom to which the MeO group is attached. The regioselectivity of this attack depends on the difference in the free enthalpies of activation leading to MeO isomers, and correlates with differences in charge distributions on the 2 C atoms.

Journal of the American Chemical Society published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Application of 2,3-Dibromo-2,3-dimethylbutane.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Chu, Edith Ju-Hwa published the artcileSymmetrical diaryldialkylethanediols. I. 2,3-Diphenyl-2,3-butanediol, Application of 2,3-Dibromo-2,3-dimethylbutane, the publication is Journal of the Chinese Chemical Society (Peking) (1942), 190-5, database is CAplus.

Bz₂ (0.0642 g. mol.) was added to 100 cc. of anhydrous Et₂O containing the Grignard reagent prepared from 0.37 g. mol. of Mg and 0.264 g. mol. of MeI. After the vigorous reaction had subsided, the mixture was refluxed for 3 hrs. and then hydrolyzed with 40 g. of NH₄Cl in 200 cc. cold H₂O. The crude 2,3-diphenyl-2,3-butanediol (I) was extracted from the reaction mixture with Et₂O and C₆H₆ and crystallized from alc., m. 118° (52% yield). Distillation of the mother liquor yielded α-methyl-α-phenylpropiophenone (II), m. 45° b. 307°. An alternative method for preparing I was to dissolve 0.036 g. mol. of PhCOMe (III) in 20 cc. of iso-PrOH and expose to sunlight for 1 month. After removal of the solvent, a quant. yield of a mixture of the high-and low-melting modifications of I was obtained, m. 84° (not sharp). A separation of the modifications was effected by fractional crystallization from CCl₄, the high-melting modification being less soluble Poor yields of I were obtained when III was reduced with Na or Mg amalgam. I (0.0144 g. mol.) was boiled with 5 cc. of HOAc containing a few crystals of iodine for 1 hr. The reaction mixture was poured into aqueous NaHSO₃ and extracted with Et₂O. From the Et₂O, II was obtained in 89% yield, m. 41-2° b₆₁₀ 300-1°. Oxime, m. 151.2-2.2° (from alc.). I (0.0023 g. mol.) refluxed with 5 cc. of Ac₂O for 1.5 hrs. yielded a mixture of II and unreacted I.

Journal of the Chinese Chemical Society (Peking) published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Application of 2,3-Dibromo-2,3-dimethylbutane.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Rossi, Renzo published the artcileSelective and efficient syntheses of phototoxic 2,2′:5′,2”-terthiophene derivatives bearing a functional substituent in the 3′- or the 5-position, HPLC of Formula: 69361-41-7, the publication is Tetrahedron (1991), 47(39), 8443-60, database is CAplus.

Efficient and selective procedures were developed to prepare on a medium scale several phototoxic 2,2′:5′:2″-terthiophene derivatives of general formula 2 (X = OEt, SMe) and 3 [Y = CHF₂, OMe, Br, CO₂Et, CONHCH₂CHMe₂, CH:CHCO₂Et-(E), CH:CHCONHCH₂CHMe₂-(E), CC-CH₂CH₂CH:CHCONHCH₂CHMe₂-(E)] which are characterized by a functional substituent in the 3′- or the 5-position. Most of these procedures, which are based on the construction of the 2,2′:5′,2”-terthiophene moiety and involve palladium-mediated carbon-carbon bond forming reactions, overcome synthetic difficulties found in the synthesis of 2 and 3 starting from 2,2′:5′,2”-terthiophene 1 (R¹-R⁶ = H).

Tetrahedron published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C7H13BrSi, HPLC of Formula: 69361-41-7.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Ebert, Max published the artcileJoint Venture of Metal Cluster and Amphiphilic Cationic Minidendron Resulting in Near Infrared Emissive Lamellar Ionic Liquid Crystals, SDS of cas: 143-15-7, the publication is Chemistry – A European Journal (2022), 28(3), e202103446, database is CAplus and MEDLINE.

Red-near-IR emissive hybrid materials obtained with phosphorescent octahedral Mo cluster anions electrostatically associated with amphiphilic guanidinium minidendrons are presented. Polarized optical microscopy and x-ray anal. show that while the minidendron chloride salts self-organize into columnar phases, their association with the dianionic metal cluster leads to layered phases. Steady-state and time-resolved emission studies demonstrate the influence of the minidendron alkyl chain length on the phosphorescence of the metal cluster core.

Chemistry – A European Journal published new progress about 143-15-7. 143-15-7 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 1-Bromododecane, and the molecular formula is C12H25Br, SDS of cas: 143-15-7.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Sokolsky, Alexander published the artcileSynthesis of a C(1)-C(23) Fragment for Spirastrellolide E: Development of a Mechanistic Rationale for Spiroketalization, Safety of (4-Bromobut-1-yn-1-yl)trimethylsilane, the publication is Organic Letters (2015), 17(8), 1898-1901, database is CAplus and MEDLINE.

Synthetic anal. of spirastrellolide E envisioned to entail a cross-metathesis union of the northern and southern hemispheres followed by a Sharpless epoxidation/methylation sequence to achieve the C(22,23) stereogenicity leads to the design of a C(1)-C(23) advanced southern hemisphere, I, exploiting a gold-catalyzed directed spiroketalization as a key step. Stereochem. anal. of this strategic transformation provides insight on the impact of the directing group carbinol stereogenicity on the reaction efficiency and, in turn, permits the conversion of the minor isomer of the spiroketal precursor to the requisite congener for successful spiroketalization.

Organic Letters published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C13H16O2, Safety of (4-Bromobut-1-yn-1-yl)trimethylsilane.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Shi, Qingzhao published the artcileSolubilization and release of fragrance agents in aqueous solution of carbon dioxide switchable surfactants, Application of 1-Bromododecane, the publication is Journal of Surfactants and Detergents (2022), 25(2), 245-253, database is CAplus.

This study describes the enhancement in the solubility and controlled-release of fragrance agents (menthol, four n-alkanols, and three aromatic esters) using three CO₂ switchable surfactants (N-alkylimidazolium bicarbonates). The surfactants significantly improved the solubility of fragrance agents in water. N-Dodecylimidazolium bicarbonate was the most effective surfactant to solubilize menthol. A stability test indicated that the surfactant could stably disperse menthol in water. Moreover, the surfactants improved the solubility of n-alkanols to different levels, however, the solubility of the aromatic esters equally. The release of menthol from the surfactant solution under N₂ at different durations of bubbling time, temperatures, and flow velocities were studied.

Journal of Surfactants and Detergents published new progress about 143-15-7. 143-15-7 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 1-Bromododecane, and the molecular formula is C14H21BO2, Application of 1-Bromododecane.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Anand, Radhika published the artcileStereoselective Synthesis of Nonpsychotic Natural Cannabidiol and Its Unnatural/Terpenyl/Tail-Modified Analogues, Formula: C12H25Br, the publication is Journal of Organic Chemistry (2022), 87(7), 4489-4498, database is CAplus and MEDLINE.

Here, we report a three-step concise and stereoselective synthesis route to one of the most important phytocannabinoids, namely, (-)-cannabidiol (-CBD), from inexpensive and readily available starting material R-(+)-limonene. The synthesis involved the diastereoselective bifunctionalization of limonene, followed by effective elimination leading to the generation of key chiral p-mentha-2,8-dien-1-ol. The chiral p-mentha-2,8-dien-1-ol on coupling with olivetol under silver catalysis provided regiospecific (-)-CBD, contrary to reported ones which gave a mixture The newly developed approach was further extended to its structural analogs cannabidiorcin and other tail/terpenyl-modified analogs. Moreover, its opposite isomer (+)-cannabidiol was also successfully synthesized from S-(-)-limonene.

Journal of Organic Chemistry published new progress about 143-15-7. 143-15-7 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 1-Bromododecane, and the molecular formula is C12H25Br, Formula: C12H25Br.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Richard, Jean-Alexandre published the artcileA Chiral-Pool-Based Approach to the Core Structure of (+)-Hyperforin, Product Details of C7H13BrSi, the publication is European Journal of Organic Chemistry (2012), 2012(3), 484-487, S484/1-S484/38, database is CAplus.

Asym. entry to the bicyclic core structure I of (+)-hyperforin is presented. The developed synthetic strategy features a carefully orchestrated stereochem. relay from the single chiral center residing within (-)-Wieland-Miescher ketone and an intramol. aldol reaction to cast the [3.3.1] bicyclic scaffold found in a diverse array of polycyclic polyprenylated acylphloroglucinols.

European Journal of Organic Chemistry published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C7H13BrSi, Product Details of C7H13BrSi.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Wang, Xiaosha published the artcilePrecise fluorination of polymeric donors towards efficient non-fullerene organic solar cells with balanced open circuit voltage, short circuit current and fill factor, Formula: C6HBrF4O, the publication is Journal of Materials Chemistry A: Materials for Energy and Sustainability (2021), 9(26), 14752-14757, database is CAplus.

Three polymer donors named Qx-8F, Qx-10F, and Qx-12F, with similar chem. structures, were synthesized. The energy level of these donors is manipulated by precisely controlling the fluorination sites. We demonstrate that the exciton dissociation efficiency is gradually enhanced from Qx-8F:Y6 to Qx-12F:Y6, leading to improved open circuit voltage VOC and short circuit c.d. JSC for donors with a higher degree of fluorination. Simultaneously, the trap-assisted recombination or bimol. recombination intensity is reduced, while the extraction rate is enhanced because of increased charge carrier mobilities, leading to an increase in fill factor for donors with higher amount of fluorine atoms. The optimized device based on Qx-12F with the most fluorine atoms and the non-fullerene acceptor Y6 shows the highest power conversion efficiency of 15.21%, with a VOC of 0.85 V, JSC of 24.55 mA cm-2, and fill factor of 72.88%. It is further demonstrated that the optimized ternary device based on the Qx-12F:PM6:Y6 blend provides a power conversion efficiency of 16.32%.

Journal of Materials Chemistry A: Materials for Energy and Sustainability published new progress about 1998-61-4. 1998-61-4 belongs to bromides-buliding-blocks, auxiliary class Fluoride,Bromide,Benzene,Phenol, name is 4-Bromo-2,3,5,6-tetrafluorophenol, and the molecular formula is C65H82N2O18S2, Formula: C6HBrF4O.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Dieter, R. Karl published the artcileAsymmetric Synthesis of Enantioenriched (+)-Elaeokanine A, Application In Synthesis of 69361-41-7, the publication is Journal of Organic Chemistry (2006), 71(15), 5674-5678, database is CAplus and MEDLINE.

The key transformation in the total synthesis of (+)-elaeokanine A (I, R = COCH₂Et) was accomplished by asym. deprotonation of N-Boc pyrrolidine, followed by the reaction of the in situ generated enantioenriched stereogenic cuprate reagent with (E)-4-bromo-1-iodo-1-trimethylsilyl-1-butene with retention of configuration. N-Boc deprotection, followed by a one-pot olefin isomerization and intramol. amine alkylation afforded bicyclic vinyl bromide I (R = Br) that was converted into (+)-elaeokanine A by sequential halogen metal exchange and reaction of the organolithium reagent with N-butanoylmorpholine.

Journal of Organic Chemistry published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C7H13BrSi, Application In Synthesis of 69361-41-7.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary