Day: November 21, 2022

Hargrave, Jonathan D. published the artcileCatalytic Enantioselective Dieckmann-Type Annulation: Synthesis of Pyrrolidines with Quaternary Stereogenic Centers, Application of (R)-5,5′-Bis(diphenylphosphino)-2,2,2′,2′-tetrafluoro-4,4′-bi-1,3-benzodioxole, the publication is Angewandte Chemie, International Edition (2010), 49(10), 1825-1829, S1825/1-S1825/70, database is CAplus and MEDLINE.

A Dieckmann-type cyclization coupled to an arylation reaction was used to synthesize the title compounds, e.g., I, with up to 96% ee from amine-tethered ester-substituted acrylates. The presence of a coordinating functionality in the substrate, e.g., II, induces a competition between cyclization and elimination pathways that is influenced by the nature of the chiral ligand. A mechanistic rationale is proposed to account for these observations.

Angewandte Chemie, International Edition published new progress about 503538-69-0. 503538-69-0 belongs to dioxole, auxiliary class (Atropisomeric Bisphosphine Ligands, name is (R)-5,5′-Bis(diphenylphosphino)-2,2,2′,2′-tetrafluoro-4,4′-bi-1,3-benzodioxole, and the molecular formula is C38H24F4O4P2, Application of (R)-5,5′-Bis(diphenylphosphino)-2,2,2′,2′-tetrafluoro-4,4′-bi-1,3-benzodioxole.

Referemce:
https://en.wikipedia.org/wiki/1,3-Benzodioxole,
Dioxole | C3H4O2 – PubChem

Langlois, Jean-Baptiste published the artcileCopper-catalyzed asymmetric allylic alkylation of racemic cyclic substrates: Application of dynamic kinetic asymmetric transformation (DYKAT), Quality Control of 503538-69-0, the publication is Advanced Synthesis & Catalysis (2010), 352(2+3), 447-457, database is CAplus.

The copper-catalyzed asym. allylic alkylation (AAA) is of great interest in organic synthesis. This reaction was extensively studied using a broad range of substrates, ligands and organometallic reagents. However, the use of racemic substrates was still limited. Although some processes of kinetic resolution are reported in the literature, no examples of quant. deracemization are described as is the case for the Pd-catalyzed allylic alkylation. The development and results of the copper-catalyzed AAA is reported. High enantioselectivities, scope of the reaction and mechanistic considerations are reported herein.

Advanced Synthesis & Catalysis published new progress about 503538-69-0. 503538-69-0 belongs to dioxole, auxiliary class (Atropisomeric Bisphosphine Ligands, name is (R)-5,5′-Bis(diphenylphosphino)-2,2,2′,2′-tetrafluoro-4,4′-bi-1,3-benzodioxole, and the molecular formula is C38H24F4O4P2, Quality Control of 503538-69-0.

Referemce:
https://en.wikipedia.org/wiki/1,3-Benzodioxole,
Dioxole | C3H4O2 – PubChem

Anteunis, M. published the artcileNuclear magnetic resonance experiments on ketals. III. Proton magnetic resonance (P.M.R.) spectrum and conformations of the glycol ketal of 1,2-propanediol with acetone and acetaldehyde, Safety of 2,2,4-Trimethyl-1,3-dioxolane, the publication is Bulletin des Societes Chimiques Belges (1964), 73(11-12), 889-97, database is CAplus.

cf. CA 61, 10570h. The H N.M.R. (P.M.R.) spectra of 2,2,4-trimethyl-1,3-dioxolane (I) and cis- and trans-2,4-dimethyl-1,3-dioxolane (II) were determined and analyzed. The chem. shifts are in accordance with a half-chair conformation. The 1,3-H-Me interaction causes an upfield shift of ∼0.15 ppm. when the 2 are cis to one another. A similar shift of 0.05 ppm. was noted for a cis-1,3-Me-Me interaction. In I and cis-II, long-range coupling between the 4-Me and the methylene H cis to it is observed. I (b. 100°) was prepared from Me₂C(OMe)₂ (0.3 moles), propanediol (III) (0.2 moles), and H₂SO₄ catalyst. II was prepared by slow distillation of MeCH0 from acidified paraldehyde into III. Separation of the product by gas-liquid chromatography gave cis-II, b. 91.8°, n²⁵ 1.3945, d_23.6 0.92786, m. 55-60°; and trans-II, b. 89.5°, n²⁵ 1.3928; d_23.0 0.91570. meso4,5-Dimethyl-1,3-dioxolane (b. 104°) was prepared by azeotropic H₂O removal with C₆H₆ from a mixture of monobutanediol and (HCHO)_x. The HCHO ketal of 4,5-trimethylene-1,3-dioxolane prepared similarly b. 80°/18 mm.

Bulletin des Societes Chimiques Belges published new progress about 1193-11-9. 1193-11-9 belongs to dioxole, auxiliary class Dioxolanes, name is 2,2,4-Trimethyl-1,3-dioxolane, and the molecular formula is C6H12O2, Safety of 2,2,4-Trimethyl-1,3-dioxolane.

Referemce:
https://en.wikipedia.org/wiki/1,3-Benzodioxole,
Dioxole | C3H4O2 – PubChem

Alikarami, Mohammad published the artcileOxidative deprotection of trimethylsilyl and tetrahydropyranyl ethers, acetals and ketals with N,N’-dibenzyl-1,4-diazoniabicyclo[2.2.2]octane peroxodisulfate under non-aqueous conditions, Name: 1,4-Dioxaspiro[4.5]decane, the publication is Organic Chemistry: An Indian Journal (2013), 9(11), 463-468, database is CAplus.

An efficient and convenient conversion of trimethylsilyl and tetrahydropyranyl ethers, acetals and ketals to the corresponding carbonyl compounds with N,N’-dibenzyl-1,4-diazoniabicyclo[2.2.2]octane peroxodisulfate under non-aqueous conditions is described.

Organic Chemistry: An Indian Journal published new progress about 177-10-6. 177-10-6 belongs to dioxole, auxiliary class Dioxolane,Spiro, name is 1,4-Dioxaspiro[4.5]decane, and the molecular formula is C8H14O2, Name: 1,4-Dioxaspiro[4.5]decane.

Referemce:
https://en.wikipedia.org/wiki/1,3-Benzodioxole,
Dioxole | C3H4O2 – PubChem