Month: November 2022

Lubman, David M. published the artcileMass spectrometry of aromatic molecules with resonance-enhanced multiphoton ionization, Quality Control of 52358-73-3, the publication is Analytical Chemistry (1982), 54(4), 660-5, database is CAplus.

The results of 2 classes of experiments with laser sources demonstrate the anal. potential of multiphoton-ionization mass spectroscopy. The 1st class of experiments demonstrates the effect of wavelength and power on the multiphoton ionization of mols. in effusive thermal beams. Valuable anal. features of such ionization processes are discussed for a variety of compounds which can be ionized by the absorption of 2 UV photons. The 2nd class of experiments demonstrates how the use of multiphoton ionization with a cooled supersonic beam can result in the very specific ionization of similar mols. Cooled mols. in supersonic beams have significantly different ionization spectra, making possible the identification of the components of interest.

Analytical Chemistry published new progress about 52358-73-3. 52358-73-3 belongs to bromides-buliding-blocks, auxiliary class Bromide,Naphthalene, name is 1,3-Dibromonaphthalene, and the molecular formula is C10H6Br2, Quality Control of 52358-73-3.

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

Bestman, HansJuergen published the artcileReactions with phosphinealkylenes. VII. Olefins and ketones by autoxidation of phosphinealkylenes, Quality Control of 594-81-0, the publication is Chemische Berichte (1963), 96(7), 1899-908, database is CAplus.

cf. CA 58, 13788g. Phosphinealkylenes of the type RCH:PPH₃ (R = alkyl) are oxidized by O to olefins and Ph₃PO. Phosphinealkylenes of the type RR’C:PPh₃ (I) yield with O the corresponding ketones. If the autoxidation of the I is interrupted after consumption of 1 O, olefins can also be formed by the Wittig reaction of the resulting ketone with unoxidized I. Ph₃P (26 g.) and 20 g. EtMeCHBr heated 18 hrs. at 100-20° in a sealed tube, and the powd. product boiled 2-3 times with C₆H₆ yielded 38 g. [iso-BuPPh₃]Br (II), m. 235-8° Ph₂P (13 g.) and 9.0 g. hexahydrobenzyl bromide heated 24 hrs. at 140-50° in a sealed tube, and the powd. product washed with pert. ether yielded 21 g. triphenylhexahydrobenzylphosphonium bromide (III), m. 225-8° (with softening from 200°). Ph₃P (26 g.) and 16 g. p-MeOC₆H₄CH₂Cl heated 1 hr. at 80-100°, and the powd. product boiled 2-3 times with C₆H₆ yielded 41 g. [p-MeOC₆H₄CH₂PPh₃]Cl (IV), m. 214-18° (CHCl₃-EtOAc). Ph₃P (26 g.) and 27 g. cyclohexyl bromide heated 60 hrs. at 140° in a sealed tube gave similarly 40 g. triphenylcyclohexylphosphonium bromide (V), m. 255-9° (CHCl₃-EtOAc). NaNH₂ (up to 25% excess) in dry NH₃ treated with the dry, powd. phosphonium salt, the NH₃ evaporated, the residue boiled about 10 min. with C_H6, MePh, Et₂O, tetrahydrofuran, etc., and the solution oxidized with O gave the corresponding oxidation products; method A. Na, K, or Li in 100 cc. absolute MeOH, EtOH, or tert-BuOH treated with an equivalent amount dry, powd. phosphonium salt gave a solution of phosphinealkylene which can be oxidized with O; method B. All operations up to the oxidation have to be performed under N or Ar. The oxidations with O were carried out in a special apparatus (described in detail) in which a measured amount O can be recirculated. [PhCH₂PPh₃]Br (18.0 g.) and 0.92 g. Na in 100 cc. absolute EtOH processed by method B, and the refluxing ylide solution treated 24 hrs. with 0 and poured into 100 cc. 10% HBr precipitated 1.46 g. trans-stilbene (VI), m. 121°; the filtrate evaporated, the residue extracted with Et₂O, the extract diluted with petr. ether, the precipitated Ph₃PO (10.3 g.) filtered off, and the filtrate distilled gave 0.84 g. cis-stilbene (VII), b₁₂ 140-2°, n²⁰_D 1.6189. Tricyclohexylbenzylphosphonium chloride (8.1 g.) treated with 0.46 g. Na in 50 cc. absolute EtOH by method B and oxidized 12 hrs. at reflux, and the mixture poured into 50 cc. 10% HBr gave 1.2 g. VI; the acidic mother liquor concentrated gave 1.2 g. unchanged phosphonium salt and 74% tricyclohexylphosphine oxide. [¹PhCH₂PPh₃]Cl treated with 0.6 g. Na and 70 cc. C₆H₆ by method A, the solution oxidized 5 hrs. at 80° (96% O consumption) and evaporated, and the residue dissolved in 30 cc. MeOH and poured into 20 cc. 10% HBr yielded 1.7 g. VI and only a small amount of VII; the mother liquor diluted with H_O precipitated 5.8 g. Ph₃PO. IV (12.5 g.), 1.2 g. Na, and 150 cc. dry C₆H₆ processed by method A, and the solution oxidized 1 hr. at room temperature (84% O consumption) yielded 1.4 g. trans-(MeOC_H4CH:)₂, m. 210-11° (MeOH-H₂O); the mother liquor evaporated and the residue triturated with petr. ether left 6.9 g. Ph₃PO; the petr. ether extract distilled yielded 0.70 g. cis-p-(MeOC₆H₄CH:)₂, b_0.1 140°, m. 35°. [EtPPh₃]Br (11.1 g.) treated by method A with 0.9 g. Na in 150 cc. dry Et₂O and oxidized 15 min. at 0% and the effluent gas (swept with N) passed into BrCHCl₃ yielded 2.7 g. (MeCHBr)₂, b₁₂ 58-62°; the Et₂O solution yielded 6.2 g. Ph₃PO₂. [PrPPh₃]Br (11.7 g.) treated by method A with 0.9 g. Na and 100 cc. MePh and oxidized 15 min. at 0° (100% O consumption) yielded 0.90 g. 3-hexene, b. 63-5°. [BuPPh₃]Br (24 g.) treated with 1.8 g. Na and 150 cc. dry tetrahydrofuran by method A and oxidized 0.5 hr. at room temperature (92% O consumption) gave 14.8 g. Ph₃PO and 2.6 g. cis- and trans-4-octene, b₇₁₀ 117-18°; dibromide b₁₀ 103°. III (22.0 g.), 1.8 g. Na, and 150 cc. C₆H₆ processed by method A and oxidized 25 min. at room temperature (100.% O consumption) yielded 11.0 g. Ph₃PO, 0.80 g. hexahydrobehzaldehyde, b₁₅ 50-3° (2,4-dinitrophenylhydrazone m. 111-13°), and 2.9 g. cis- and trans-1,2-dicyclohexylethylene. [iso-PrPPh₃]Br (VIII) (15.8 g.) treated with 0.7 g. Na and 100 cc. MePh by method A and oxidized 5 min. at room temperature (80% O consumption) and the mixture distilled into aqueous 2,4-(O₂N)₂C₆H₃NHNH₂ gave 2.2 g. 2,4-(O₂N)₂C₆H₃NHN:CMe₂, m. 126°; the distillation residue evaporated and the residue triturated with 50 cc. petr. ether yielded 2.6 g. Ph₃PO. VIII (15.2 g.) treated by method A with 1.3 g. Na in 200 cc. dry C₆H₆, 1/2 of the resulting solution oxidized with O, the O.removed with N, the remaining unoxidized reaction solution added, the mixture distilled, and the distillate treated with Br yielded 2.8 g. (Me₂CBr)₂, m. 168-71° (EtOH); the distillation residue gave 6.7 g. Ph₃PO. The same result was obtained when the oxidation was interrupted after the consumption of 1 equivalent O and the mixture was kept several hrs.; 53% yield. VIII (6.0 g.) processed with 0.5 g. Na and 100 cc. MePh by method A and oxidized 10 min. at room temperature (75% O consumption), and distilled into aqueous 2,4-(O₂N)₂C₆H₃NHNH₂.HCl yielded 2.1 g. 2,4-(O₂N)₂C₆H₃NHN:CEtMe, m. 116-17°; the residue gave 3.5 g. Ph₃PO. VIII (16.0 g.) treated by method A with 1.4 g. Na and 200 cc. dry C₆H₆, 1/2 of the resulting solution oxidized, purged with N, treated with the remaining unoxidized solution, refluxed under N until pale yellow, and evaporated, and the residue treated with 100 cc. Et₂O and cooled gave 9.6 g. Ph₃PO; the filtrate distilled yielded 1.3 g. (EtMeC:)₂, b. 95-8° [dibromide b₇₆₀ 147-50° (slight decomposition)]; the same results were obtained when the oxidation was interrupted after the consumption of 1 equivalent O; 50% yield. [MePhC:PPh₃]Br (8.9 g.) treated with 0.7 g. Na and 100 cc. dry C₆H₆ by method A and oxidized 15 min. at room temperature (98% O consumption) yielded 4.2 g. Ph₃PO; the filtrate evaporated, and the residue treated with EtOH and 2,4-(O₂N)₂C₆H₃NHNH₂ solution gave 4.1 g. 2,4-(O₂N)₂C₆H₃NHN:-CMePh, m. 248°. [Ph₂CHPPh₃]Br (7.6 g.) treated with 0.6 g. Na and 200 cc. dry C₆H₆ by method A and oxidized 8 hrs. at room temperature (95% O consumption), the C₆H₆ distilled, and the residue treated with 60 cc. petr. ether yielded 3.1 g. Ph₃PO; the filtrate evaporated and the residue treated with 2,4-(O₂N)2C₆H₃NH-NH₂.H₃PO₄ solution yielded 3.8 g. 2,4-(O₂N)2C₆H₃NHN:CPh₂, m. 238°. V (8.5 g.) treated with 0.7 g. Na and 100 cc. C₆H₆ by method A and oxidized 15 min. at room temperature (77% O consumption), and the mixture worked up in the same manner gave 3.6 g. cyclohexanone 2,4-dinitrophenylhydrazone, m. 158°.

Chemische Berichte 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, Quality Control of 594-81-0.

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

Sun, Jianwei published the artcileBronsted Acid-Promoted Cyclizations of 1-Siloxy-1,5-diynes, COA of Formula: C7H13BrSi, the publication is Journal of the American Chemical Society (2005), 127(39), 13512-13513, database is CAplus and MEDLINE.

The 1st HNTf₂-promoted 5-endo-dig cyclizations of 1-siloxy-1,5-diynes was developed, which proceed with concomitant formation of C-Hal bonds as a result of halide abstraction from a halocarbon by the intermediate alkenyl cation. E.g., reaction of RCH₂CCCH₂CH₂CCOTIPS (OTIPS = triisopropylsilanolato, R = n-C₇H₁₅) with HNTf₂/CH₂Cl₂ at -78° and allowed to warm to room temperature to give 70% yield of 2-(1-chloro-2-R-ethylidene)cyclopentanone. This process is enabled by a chemoselective activation of the more electron-rich siloxy alkyne moiety of the diyne cyclization precursor and represents an efficient and highly diastereoselective method for assembly of a range of β-halo enones.

Journal of the American Chemical Society 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 C6H5F4NO3S, COA of Formula: C7H13BrSi.

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

Harrison, Tyler J. published the artcilePyrrole Synthesis Catalyzed by AgOTf or Cationic Au(I) Complexes, Application In Synthesis of 69361-41-7, the publication is Journal of Organic Chemistry (2006), 71(12), 4525-4529, database is CAplus and MEDLINE.

Either silver trifluoromethanesulfonate or a mixture of gold(I) chloride, silver trifluoromethanesulfonate, and triphenylphosphine catalyze the formation of pyrroles from substituted β-alkynyl ketones and amines. The reactions proceed by using 5 mol % of catalyst with yields of isolated pyrroles ranging from 13% to 92%. Sixteen examples are used to compare the effectiveness of each catalyst. Example compounds thus prepared included also cyclopenta[b]pyrrole derivatives tetrahydro(methyl)indolizine. and dihydro-1H-pyrrolizine derivatives

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

Zhang, Huihui published the artcileRadical-Mediated Distal Ipso-Migration of O/S-Containing Heteroaryls and DFT Studies for Migratory Aptitude, Category: bromides-buliding-blocks, the publication is Organic Letters (2020), 22(15), 5947-5952, database is CAplus and MEDLINE.

Herein we describe an efficient distal ipso-migration of O- and S-containing heteroaryls and the radical heteroarylation of unactivated alkenes. The migration is triggered by various fluoroalkyl radicals, leading to valuable multifunctionalized ketones. The comparisons of migratory aptitude for O-/S-containing heteroaryls are comprehensively investigated. The origin of the chemoselective migration could be partially attributed to the discrepancy in the energy level of the LUMO of each heteroaryl group.

Organic Letters published new progress about 401-55-8. 401-55-8 belongs to bromides-buliding-blocks, auxiliary class Fluoride,Bromide,Aliphatic hydrocarbon chain,Ester, name is Ethylbromofluoroacetate, and the molecular formula is C10H16Br3N, Category: bromides-buliding-blocks.

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

Suri, Deepa published the artcileKinetics and mechanism of the oxidation of formic and oxalic acids by benzyltrimethylammonium tribromide, Quality Control of 111865-47-5, the publication is Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry (1998), 37B(5), 448-452, database is CAplus.

The oxidation of formic and oxalic acids by benzyltrimethylammonium tribromide (BTMAB) leads to the formation of carbon dioxide. The reaction is first order with respect to BTMAB. Michaelis-Menten type kinetics are observed with respect to substrate. The values of the formation constants for the organic acid-BTMAB complexes and the rates of their decomposition, at different temperatures, have been determined Oxidation of α-deuterioformic acid indicated the presence of a primary kinetic isotope effect (k_H/k_D = 6.03 at 298 K). With an increase in the polarity of solvent, the formation constants for the complexes decrease however, their rates of decomposition increase. Suitable mechanisms involving the formation of acyclic and cyclic intermediates in the oxidations of formic and oxalic acids resp., have been proposed.

Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry published new progress about 111865-47-5. 111865-47-5 belongs to bromides-buliding-blocks, auxiliary class Benzenes, name is Mono(N,N,N-trimethyl-1-phenylmethanaminium) tribromide, and the molecular formula is C6H8O3, Quality Control of 111865-47-5.

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

Sankhla, Rekha published the artcileCorrelation analysis of reactivity in the oxidation of substituted benzylamines by benzyltrimethylammonium tribromide, Product Details of C10H16Br3N, the publication is Indian Journal of Chemistry, Section A: Inorganic, Bio-inorganic, Physical, Theoretical & Analytical Chemistry (2002), 41A(3), 541-546, database is CAplus.

The oxidation of benzylamine and twenty-seven ortho-, meta- and para-monosubstituted benzylamines by benzyltrimethylammonium tribromide (BTMAB), in dimethylsulfoxide (DMSO), gives corresponding aldimines. The reaction is first order with respect to both BTMAB and the amine. The oxidation of deuterated benzylamine exhibited a substantial kinetic isotope effect. Addition of benzyltrimethylammonium bromide does not affect the rate. Tribromide ion was postulated as the reactive oxidizing species. The rates of the oxidation of para- and meta-substituted benzylamines showed excellent correlation in terms of both Taft’s dual substituent-parameter and Charton’s triparametric LDR equations, whereas the ortho-substituted compounds exhibited the best correlation with the Charton’s tetraparametric LDRS equation. The oxidation of para-substituted benzylamines is more susceptible to the delocalization effect than is the oxidation of ortho- and meta-substituted compounds, which display a greater dependence on the field effect. The low pos. value of the η suggests an electron-deficient center in the rate-determining transition state with less charge separation A suitable mechanism was proposed.

Indian Journal of Chemistry, Section A: Inorganic, Bio-inorganic, Physical, Theoretical & Analytical Chemistry published new progress about 111865-47-5. 111865-47-5 belongs to bromides-buliding-blocks, auxiliary class Benzenes, name is Mono(N,N,N-trimethyl-1-phenylmethanaminium) tribromide, and the molecular formula is C10H16Br3N, Product Details of C10H16Br3N.

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

Mehla, Satish K. published the artcileCorrelation analysis of reactivity in the oxidation of substituted benzaldehydes by benzyltrimethylammonium tribromide, Category: bromides-buliding-blocks, the publication is Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry (2002), 41B(4), 832-838, database is CAplus.

The oxidation of benzaldehyde and thirty-five monosubstituted benzaldehydes by benzyltrimethylammonium tribromide (BTMAB) in aqueous acetic acid gives the corresponding benzoic acids. The reaction is first order with respect to each the benzaldehyde and BTMAB. The reaction failed to induce the polymerization of acrylonitrile. There is no effect of benzyltrimethylammonium chloride on the reaction rate. The oxidation of [²H]benzaldehyde (PhCDO) indicated the presence of a substantial kinetic isotope effect. The effect of solvent composition indicated that the reaction rate increases with an increase in the polarity of the solvent. The rates of oxidation of meta- and para-substituted benzaldehydes are correlated in terms of Charton’s triparametric LDR equation whereas the oxidation of ortho-substituted benzaldehydes are correlated with tetraparametric LDRS equation. The oxidation of para- substituted benzaldehydes is more susceptible to the delocalization effect than is the oxidation of ortho-and meta-substituted compounds, which display a greater dependence on the field effect. The pos. value of η suggests an electron-deficient reaction center in the rate-determining step. The reaction is subjected to steric hindrance by the ortho-substituents.

Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry published new progress about 111865-47-5. 111865-47-5 belongs to bromides-buliding-blocks, auxiliary class Benzenes, name is Mono(N,N,N-trimethyl-1-phenylmethanaminium) tribromide, and the molecular formula is C10H16Br3N, Category: bromides-buliding-blocks.

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

Goyal, Archana published the artcileKinetics and mechanism of the oxidation of methionine by benzyltrimethylammonium tribromide, Formula: C10H16Br3N, the publication is Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry (2003), 42B(9), 2129-2132, database is CAplus.

The oxidation of methionine (MTN) by benzyltrimethylammonium tribromide (BTMAB), in 1:1 aqueous acetic acid, gives the corresponding sulfoxide. The reaction is first order with respect to each the methionine and BTMAB. The oxidation of MTN in an atm. of N, failed to induce the polymerization of acrylonitrile. An addition of benzyltrimethylammonium chloride has no effect on the rate of oxidation The rates of oxidation were determined at different temperatures and the activation parameters were calculated The reaction rate increases with an increase in the polarity of the medium. Tribromide ion is postulated as the reactive oxidizing species. Suitable mechanism for the reaction is postulated.

Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry published new progress about 111865-47-5. 111865-47-5 belongs to bromides-buliding-blocks, auxiliary class Benzenes, name is Mono(N,N,N-trimethyl-1-phenylmethanaminium) tribromide, and the molecular formula is C10H16Br3N, Formula: C10H16Br3N.

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

Goswami, Garima published the artcileKinetics and mechanism of oxidation of aliphatic aldehydes by benzyltrimethylammonium tribromide, HPLC of Formula: 111865-47-5, the publication is Journal of Chemical Research, Synopses (1999), 176-177, 813-833, database is CAplus.

The oxidation of aliphatic aldehydes by benzyltrimethylammonium tribromide involves the formation of an intermediate complex and its subsequent decomposition in the rate-determining step to the corresponding carboxylic acid.

Journal of Chemical Research, Synopses published new progress about 111865-47-5. 111865-47-5 belongs to bromides-buliding-blocks, auxiliary class Benzenes, name is Mono(N,N,N-trimethyl-1-phenylmethanaminium) tribromide, and the molecular formula is C10H16Br3N, HPLC of Formula: 111865-47-5.

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