102632-99-5Relevant academic research and scientific papers
Allylsamarium bromide-mediated cascade cyclization of homoallylic esters. Synthesis of 2-(2-hydroxyalkyl)cyclopropanols and 2-(2-hydroxyethyl)bicyclo[2.1.1]hexan-1-ols
Shen, Mengmeng,Tu, Yawei,Xie, Guanqun,Niu, Qingsheng,Mao, Hui,Xie, Tingting,Flowers, Robert A.,Lv, Xin,Wang, Xiaoxia
, p. 52 - 61 (2015)
In continuation of our previous study on the intramolecular reductive coupling of simple homoallylic esters promoted by allylSmBr/HMPA/H2O, which afforded a facile synthesis of 2-(2-hydroxyalkyl)cyclopropanols, here we report the reductive casc
Magnesium Lewis Acid Assisted Oxidative Bromoetherification Involving Bromine Transfer from Alkyl Bromides with Aldehydes by Umpolung of Bromide
Moriyama, Katsuhiko,Nishinohara, Chihiro,Togo, Hideo
, p. 11934 - 11939 (2016)
An oxidative bromoetherification involving a bromine transfer from alkyl bromides upon reacting them with aldehydes in a Grignard reaction with a concurrent oxidation of bromide was developed to provide substituted tetrahydrofurans in high yields. This reaction, which proceeds through two types of bromine transfer, was promoted by the addition of a Br?nsted acid. Mechanistic studies suggested that a magnesium Lewis acid activates hypobromate, which is generated in situ from the reaction of bromide and Oxone to improve the electrophilicity of the bromonium ion (Br+) for the oxidative bromoetherification of alkenyl alcohols. Furthermore, the magnesium Lewis acid catalyzed oxidative bromoetherification of an alkenyl alcohol proceeded to provide a cyclization product in 92 % yield.
Allylation of Aldehydes, Aldimines and Ring Opening of Terminal Aromatic Epoxides by Scandium Triflate using Polyethylene Glycol (PEG) as an Efficient Recyclable Medium
Choudary, Boyapati M.,Jyothi, Karangula,Madhi, Sateesh,Kantam, Mannepalli L.
, p. 231 - 234 (2004)
Scandium triflate catalyzed allylation of a variety of aldehydes and aldimines using polyethylene glycol (PEG) as a recyclable reaction medium proceeds smoothly and affords corresponding homoallylic alcohols and amines in good yields. Furthermore this cat
Synthesis of a trans-chelating chiral diphosphine ligand with only planar chirality and its application to asymmetric hydrosilylation of ketones
Kuwano,Uemura,Saitoh,Ito
, p. 1327 - 1330 (1999)
Optically active diphosphine (S,S)-2,2-bis[(diethylphosphino)methyl]- 1,1-biferrocene (abbreviated to (S,S)-EtTRAP-H) was synthesized from ferrocenyloxazoline derived from-L-valinol in 47% overall yield. The new chiral ligand, (S,S)-EtTRAP-H, which coordinates to a rhodium atom in a trans-chelating manner, was effective for asymmetric hydrosilylation of ketones to give optically active secondary alcohols with up to 94% ee.
Intramolecular Diels-Alder Reaction of N-Alkyl-2-cyano-1-azadienes: A Study of the Eschenmoser Cycloreversion of Dihydrooxazines as a Route to N-Alkyl-2-cyano-1-azadienes
Motorina, Irina A.,Fowler, Frank W.,Grierson, David S.
, p. 2098 - 2105 (1997)
In connection with the development of the intramolecular Diels-Alder reaction (IMDA) of 1-azadienes, the 5,6-dihydro-4H-1,2-oxazine 12 has been evaluated as a synthon equivalent of the 2-cyano-1-azadiene system. It was found that the dihydrooxazonium salt 27, generated in situ from the cyclic hydroxamic acid derivative 26, is converted directly to azadiene 4a via tautomerization to the corresponding enamine and a particularly facile Eschenmoser type cycloreversion process. Conditions were subsequently found for the preparation of synthon 12. N-Alkylation of this intermediate with alkyl bromides in the presence of Ag+ ion also resulted in direct formation of the 2-cyano-1-azadiene products 38a-d and 4a. Microwave irradiation of a benzene solution of azadiene 4a proved to be a convenient means to effect its IMDA conversion to indolizidine 5a. To avoid decomposition of azadiene 38c, its intramolecular cycloaddition giving 40 (60%) was achieved by flash vacuum thermolysis.
Easy selective generation of (lithiomethyl)cyclopropane or homoallyllithium by a chlorine-lithium exchange
Pastor, Isidro M.,Pe?afiel, Itziar,Yus, Miguel
, p. 6870 - 6872 (2008)
The reaction of (chloromethyl)cyclopropane 5 with lithium and a catalytic amount of DTBB (5 mol %) in the presence of different carbonyl compounds [Et2CO, n-Pr2CO, (c-C3H5)2CO, (CH2)5CO, PhCOMe, t-BuCHO, i-PrCHO, PhCHO] as electrophiles in THF at -78 °C leads, after hydrolysis with water, to the corresponding cyclopropyl alcohols 6. However, when the same starting material is lithiated using naphthalene as the arene catalyst in ether at 0 °C and then reacts with the same series of electrophiles, the final hydrolysis with water yields the corresponding unsaturated alcohols 7.
Low Temperature Grignard Reactions with Pure Mg Slurries. Trapping of Cyclopropylmethyl and Benzocyclobutenylmethyl Grignard Reagents with CO2
Kuendig, Ernst Peter,Perret, Celia
, p. 2606 - 2613 (1981)
Cyclopropylmethyl bromide reacts readily at -75 deg with a Mg/THF slurry formed by evaporation of Mg in a rotating-solution reactor to yield after carbonation cyclopropyl acetic acid and 4-pentenoic acid in a ratio of 11:1.Addition of benzaldehyde to the Grignard solution again predominantly yields the addition product containing the cyclopropylmethyl unit.Using the same low temperature Grignard method, benzocyclobutenyl acetic acid is isolated upon carbonation of the Grignard reagent derived from the corresponding bromide, whereas under normal conditions o-vinylphenylacetic acid, the product corresponding to ring cleaved Grignard is obtained.
Allylation of epoxides with allylic indium reagents
Hirashita, Tsunehisa,Mitsui, Kazuma,Hayashi, Yousuke,Araki, Shuki
, p. 9189 - 9191 (2004)
Allylindium sesquihalide reacts with epoxide to give homoallyl alcohol via a 1,2-shift reaction. In contrast, allylindate gives the ring-opening product without rearrangement.
FORMATION AND REARRANGEMENT OF THE GRIGNARD REAGENT FROM 2-PHENYLCYCLOBUTYLMETHYL BROMIDE
Hill, E. Alexander,Harder, Constance L.,Wagner, Richard,Meh, David,Bowman, Richard P.
, p. 5 - 18 (1986)
Reaction of cis- or trans-2-phenylcyclobutylmethyl bromide with magnesium produces the rearranged 5-phenyl-1-penten-5-ylmagnesium compound 7 in addition to the unrearranged Grignard reagent 6.The former appears to result from very rapid rearrangement of a radical intermediate in the process of Grignard reagent formation.Rearrangement of 6 to 7 also occurs, at a rate which is accelerated by the phenyl group.
Yb(OTf)3 catalyzed highly regioselective allylation of aromatic epoxides: An efficient route to bishomoallyl alcohols
Likhar, Pravin R.,Kumar, Manyam Praveen,Bandyopadhyay, Ananda K.
, p. 3333 - 3335 (2002)
Anhydrous ytterbium(III) triflate-catalyzed ring opening of aromatic 1,2-epoxides with allyltributyltin in THF results in the formation of bishomoallyl alcohols in excellent yields and with complete regioselectivity. The results are compared with those ob
