28435-62-3Relevant articles and documents
Synthesis of Di-, Tri-, and tetrasubstituted oxetanes by rhodium-catalyzed O-H insertion and C-C bond-forming cyclization
Davis, Owen A.,Bull, James A.
supporting information, p. 14230 - 14234 (2015/02/19)
Oxetanes offer exciting potential as structural motifs and intermediates in drug discovery and materials science. Here an efficient strategy for the synthesis of oxetane rings incorporating pendant functional groups is described. A wide variety of oxetane 2,2-dicarboxylates were accessed in high yields, including functionalized 3-/4-aryl-and alkyl-substituted oxetanes and fused oxetane bicycles. Enantioenriched alcohols provided enantioenriched oxetanes with complete retention of configuration. The oxetane products were further derivatized, while the ring was maintained intact, thus highlighting their potential as building blocks for medicinal chemistry.
Bromine and iodine-cucurbit[6]uril complexes: Preparation and applications in synthetic organic chemistry
Reddy,Cavallini,Demets,Silva
supporting information, p. 2262 - 2264 (2014/06/09)
Iodine and bromine inclusion compounds were easily prepared by gas diffusion of the halogens using finely powdered CB[6]. A brown powder consisting of I2-CB[6]·4H2O and an orange one of (Br 2)4-CB[6]·10H2O were employed in several different reactions. I2-CB[6] can be used in catalytic reactions giving yields comparable to those reported in the literature. Br 2-CB[6] was effectively applied in electrophilic bromination of benzene and formation of bromohydrin. However, the radical substitution at cyclohexene could not be performed. Overall, based on these results, several applications can be envisioned for these complexes. This journal is the Partner Organisations 2014.
Enzymatic preparation of (1S,2R)- and (1R,2S)-stereoisomers of 2-halocycloalkanols
Kolodiazhna, Olga O.,Kolodiazhna, Anastasy O.,Kolodiazhnyi, Oleg I.
, p. 37 - 42 (2013/02/25)
The stereoisomers of cis-2-halocycloalkanols were resolved by a kinetically controlled transesterification with vinyl acetate in the presence of lipases in organic media. High enantioselectivities (ee >98%) and good isolated yields were obtained for all substrates using the appropriate lipase. Burkholderia cepacia lipase was the most efficient enzyme for the resolution of these substrates. The enantiomeric purities of the compounds were defined by derivatization with Mosher's acid and the absolute configurations were determined by chemical correlation.
Monobromoborane-dimethyl sulfide - A highly promising reagent for the regio- and chemoselective brominative cleavage of terminal epoxides into vicinal bromohydrins
Roy, Chandra D.,Brown, Herbert C.
, p. 139 - 145 (2008/02/11)
Monobromoborane?dimethyl sulfide (BH2Br?SMe2) is a highly regio- and chemoselective reagent useful for the brominative cleavage of the epoxy moiety into bromohydrins in the presence of alkenes, alkynes, ethers, acetals, ketals, and acetonides at 0°C, besides being an excellent hydroborating reagent. Several reactive functional groups, such as chloride, ketones, esters, nitriles, nitros, and thioethers, have been accommodated during such transformations. Although the reduction of acetophenone was completely suppressed at ?25°C, 4-chlorobenzaldehyde still underwent 12?13% reduction of an aldehydic group. CSIRO 2007.
Highly regioselective ring opening of epoxides and aziridines using (bromodimethyl)sulfonium bromide
Das, Biswanath,Krishnaiah, Maddeboina,Venkateswarlu, Katta
, p. 4457 - 4460 (2007/10/03)
Epoxides and aziridines undergo ring opening efficiently with (bromodimethyl)sulfonium bromide at room temperature to form the corresponding β-bromohydrins and β-bromoamines, respectively. The conversions are highly regioselective and afford the products in excellent yields within a short period of time.
A General Route to the Synthesis of N-Protected 1-Substituted and 1,2-Disubstituted Taurines
Xu, Jiaxi,Xu, Shu
, p. 276 - 282 (2007/10/03)
N-Benzyloxycarbonyl protected α-substituted and αβ- disubstituted taurines were synthesized from olefins and epoxides via N-benzyloxycarbonylamino alcohol thioacetates as key intermediates. They are important sulfur analogues of naturally occurring amino acids and building blocks for the synthesis of α-substituted and α,β- disubstituted β-sulfonopeptides.
Selective conversion of epoxides to vic-halo alcohols and symmetrical or unsymmetrical dihalides by triphenylphosphine/2,3-dichloro-5,6-dicyano-1,4- benzoquinone (DDQ) in the presence of quaternary ammonium halides
Iranpoor, Nasser,Firouzabadi, Habib,Aghapour, Ghasem,Nahid, Azarmidokht
, p. 1885 - 1891 (2007/10/03)
A new method is described for the efficient and selective conversion of epoxides to vic-halo alcohols or symmetrical and unsymmetrical dihalides using PPh3/DDQ/R4NX (X = Cl, Br, I) as a mixed-reagent system.
Observations on the use of triphenylphosphonium bromide as a mild and quantifiable source of hydrogen bromide for chemoselective ring opening of epoxides to bromohydrins
Afonso, Carlos A.M.,Vieira, Nuno M.L.,Motherwell, William B.
, p. 382 - 384 (2007/10/03)
The chemoselective ring opening of epoxides to bromohydrins in the presence of ketal, benzyloxymethoxy and trimethylsilyl ether functionality using triphenylphosphonium bromide is described. The preparation of a polymer supported variant is also reported.
Substrate Modification to Increase the Enantioselectivity of Hydrolases. A Route to Optically-Active Cyclic Allylic Alcohols.
Gupta, Ajay K.,Kazlauskas, Romas J.
, p. 879 - 888 (2007/10/02)
The esterase-catalyzed resolution of the cyclic allylic acetates - 1-acetyloxy-2-cyclopentene, 1-acetyloxy-2-cyclohexene, and 1-acetyloxy-2-cycloheptene - was not enantioselective.We hypothesized that this inefficiency stems from the similarity in size of the substituents at the stereocenter (CH2-CH2 vs.CH=CH).To increase the enantioselectivity, we resolved precursors to these cyclic allylic alcohols: esters of trans-2-bromocycloalkanols (C5, C6, C7).These esters had a larger difference in the size of the substituents (CH2 vs.CHBr) at the stereocenter and were efficiently resolved by both cholesterol esterase and lipase from Pseudomonas cepacia (Amano P, PCL).A synthetic-scale resolution with PCL yielded the (1S,2S)-1-butanoyloxy-2-bromocycloalkanes in >98percent ee.Heating with DBU to eliminate HBr, followed by reduction with LiAlH4 to cleave the ester, yielded the allylic alcohols (S)-(-)-2-cyclopenten-1-ol (65percent ee), (S)-(-)-2-cyclohexen-1-ol (>99percent ee), and (S)-(-)-2-cyclohepten-1-ol (>98percent ee).
