19218-94-1Relevant articles and documents
Contra-thermodynamic Olefin Isomerization by Chain-Walking Hydroboration and Dehydroboration
Bloomer, Brandon,Butcher, Trevor W.,Ciccia, Nicodemo R.,Conk, Richard J.,Hanna, Steven,Hartwig, John F.
supporting information, p. 1005 - 1010 (2022/02/10)
We report a dehydroboration process that can be coupled with chain-walking hydroboration to create a one-pot, contra-thermodynamic, short-or long-range isomerization of internal olefins to terminal olefins. This dehydroboration occurs by a sequence comprising activation with a nucleophile, iodination, and base-promoted elimination. The isomerization proceeds at room temperature without the need for a fluoride base, and the substrate scope of this isomerization is expanded over those of previous isomerizations we have reported with silanes.
The synthesis of long-chain α-alkyl-β-hydroxy esters using allylic halides in a Frater-Seebach alkylation
Khan, Ashna A.,Chee, Stephanie H.,Stocker, Bridget L.,Timmer, Mattie S. M.
supporting information; experimental part, p. 995 - 1002 (2012/03/27)
The Frater-Seebach alkylation is a highly efficient means to diastereoselectively introduce α-substituents to chiral β-hydroxy esters, however, the yields of reactions in which longer chain alkyl halides are used can be disappointing. To provide a more robust protocol for the alkylation of β-hydroxy esters, we prepared a variety of long-chain allylic iodides with the view that the greater reactivity of the allylic system would lead to enhanced efficiency. Indeed, for all substrates studied, the yield of the α-alkylation was greatly improved for the unsaturated allylic halides compared to their analogous saturated counterparts. Our methodology thus provides an improved means by which to access a variety of important lipophilic compounds such as mycolic acids, which are found on the cell wall of M. tuberculosis. An improved methodology for the introduction of α-substituents to chiral β-hydroxy esters using Frater-Seebach methodology is presented. Long-chain allylic iodides resulted in better yields for the α-alkylation compared to their saturated counterparts. This methodology provides an improved means by which to access a variety of important lipophilic compounds such as mycolic acids. Copyright
Synthesis of all the six components of the female-produced contact sex pheromone of the German cockroach, Blattella germanica (L.)
Mori, Kenji
, p. 4060 - 4071 (2008/09/20)
All of the following six components of the female sex pheromone of the German cockroach, Blattella germanica (L.) were synthesized: (3S,11S)-3,11-dimethyl-2-nonacosanone (1), its 29-hydroxy derivative 2, its 29-oxo derivative 3, (3S,11S)-3,11-dimethyl-2-heptacosanone (4), its 27-hydroxy derivative 5, and its 27-oxo derivative 6. Both the enantiomers of citronellal were employed as the chiral sources and Wacker oxidation was employed for the introduction of the carbonyl group at C-2.
Novel synthesis of substituted pyrrolidines and piperidines via radical addition-ionic cyclization reaction of oxime ethers
Miyata, Okiko,Takahashi, Shinya,Tamura, Akira,Ueda, Masafumi,Naito, Takeaki
, p. 1270 - 1284 (2008/09/17)
We have developed a novel synthetic route to nitrogen-containing heterocycles via radical addition-ionic cyclization reaction. Treatment of oxime ethers carrying the tosyloxy group with Et3B and alkyl iodide in the presence of Lewis acid gave the substituted pyrrolidines and piperidines. The reaction of oxime ethers carrying the methoxycarbonyl group proceeded under the same conditions to give the amino esters, which were easily converted into the corresponding lactams by the treatment with concd HCl. On the other hand, the oxime ether bearing the phenoxycarbonyl group afforded directly alkylated lactams under the radical reaction conditions. The utility of this domino reaction was demonstrated by the synthesis of (±)-bgugaine and the formal synthesis of 5,8-disubstituted indolizidine alkaloids.
Novel Biodegradable Pyridinium Amphiphiles for Gene Delivery
Pijper, Dirk,Bulten, Erna,Smisterova, Jarmila,Wagenaar, Anno,Hoekstra, Dick,Engberts, Jan B. F. N.,Hulst, Ron
, p. 4406 - 4412 (2007/10/03)
Biodegradable synthetic cationic pyridinium-based amphiphiles (SAINTs) prove to be promising non-viral carrier systems for delivery of DNA into eukaryotic cells. Six novel SAINTs were synthesised from 3,5-pyridinedicarboxylic acid as starting material, with two ester groups as linkers between the cationic headgroup and the hydrophobic tails. The vesicle-forming properties of the amphiphiles were studied by differential scanning calorimetry and transmission electron microscopy, whereas the hydrolysis of the diesters in water was investigated by NMR spectroscopy. Finally, the transfection potential and cytotoxicity were determined on COS-7 and HepG-2 cells in culture. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
Deiodinative fluorination of alkyl iodide with p-iodotoluene difluoride
Sawaguchi, Masanori,Hara, Shoji,Nakamura, Yutaka,Ayuba, Shinichi,Fukuhara, Tsuyoshi,Yoneda, Norihiko
, p. 3315 - 3319 (2007/10/03)
Oxidative fluorination of alkyl iodides with p-iodotoluene difluoride (4) was carried out. In the presence of Et3N-4HF, the fluorination reaction of prim-alkyl iodides selectively took place at the iodine position under mild conditions to give the corresponding alkyl fluorides in good yields.
PREPARATION OF ALKYL HALIDES VIA ORGANOTELLURIUMS
Chikamatsu, Kiyofumi,Otsubo, Tetsuo,Ogura, Fumio,Yamaguchi, Hachiro
, p. 1081 - 1084 (2007/10/02)
The conversion of phenyltelluroalkanes to haloalkanes was studied in connection with the homologation of alkyl halides.Similar reactions of 1,1-bis(phenyltelluro)alkanes provided a new synthetic method of aldehydes.