- A Highly Efficient Method for the Bromination of Alkenes, Alkynes and Ketones Using Dimethyl Sulfoxide and Oxalyl Bromide
-
The pairing of DMSO and oxalyl bromide is reported as a highly efficient brominating reagent for various alkenes, alkynes and ketones. This bromination approach demonstrates remarkable advantages, such as mild conditions, low cost, short reaction times, provides excellent yields in most cases and represents a very attractive alternative for the preparation of dibromides and α-bromoketones.
- Ding, Rui,Li, Jiaqi,Jiao, Wenyi,Han, Mengru,Liu, Yongguo,Tian, Hongyu,Sun, Baoguo
-
p. 4325 - 4335
(2018/11/21)
-
- One-Pot Strategy for Thiazoline Synthesis from Alkenes and Thioamides
-
A convenient synthesis of a privileged pharmaceutical motif, thiazoline is accomplished. This reaction utilizes simple and readily available alkene and thioamide substrates in an intermolecular fashion via a simple one-pot procedure. A wide range of functional groups is tolerated, and the thiazoline product has been further utilized for the synthesis of the corresponding β-aminothiol and thiazole from routine hydrolysis and oxidation protocols.
- Alom, Nur-E,Wu, Fan,Li, Wei
-
supporting information
p. 930 - 933
(2017/02/26)
-
- Novel One-Pot Synthetic Method for Propargyl Alcohol Derivatives from Allyl Alcohol Derivatives
-
An efficient one-pot procedure for the synthesis of propargyl alcohol derivatives from allyl alcohol derivatives has been developed. The key to this transformation from a C-C double bond to a C-C triple bond is that hydrogen bromide elimination from 1,2-dibromoalkanes that contain a neighboring oxygen functional group is promoted by the inductive electron-withdrawing effect of the oxygen functional group. In the one-pot reaction, tetrabutylammonium hydroxide was the best base, and the addition of molecular sieves 13X also promoted the reaction.
- Kutsumura, Noriki,Inagaki, Mai,Kiriseko, Akito,Saito, Takao
-
p. 1844 - 1850
(2015/06/30)
-
- Bromination of olefins with HBr and DMSO
-
A simple and inexpensive methodology is reported for the conversion of alkenes to 1,2-dibromo alkanes via oxidative bromination using HBr paired with dimethyl sulfoxide, which serves as the oxidant as well as cosolvent. The substrate scope includes 21 olefins brominated in good to excellent yields. Three of six styrene derivatives yielded bromohydrins under the reaction conditions.
- Karki, Megha,Magolan, Jakob
-
p. 3701 - 3707
(2015/04/22)
-
- PRECURSOR COMPOUNDS AND METHODS FOR MAKING SAME
-
The present invention relates to a method of obtaining radiopharmaceutical precursors, and in particular precursors to protected amino acid derivatives, which are used as precursors for production of radiolabelled amino acids for use in in vivo imaging procedures, such as positron emission tomography (PET).
- -
-
Paragraph 00044-00049
(2013/03/26)
-
- An economical and convenient synthesis of vinyl sulfones
-
A general process for the efficient synthesis of vinyl sulfones has been developed using commercially available sulfinic acid sodium salts and dibromides. A variety of phenyl and methyl vinyl sulfones have been formed in good yields, in the absence of any catalyst. Georg Thieme Verlag Stuttgart.
- Guan, Zheng-Hui,Zuo, Wei,Zhao, Lian-Biao,Ren, Zhi-Hui,Liang, Yong-Min
-
p. 1465 - 1470
(2008/02/05)
-
- Carbon-functionalized 1,4 7-Trithiacyclononanes: Synthesis, Molecular Mechanics and Co-ordination Chemistry
-
A series of functionalized analogues of 1,4,7-trithiacyclononane has been synthesized and the effects of functionalization on their co-ordination chemistry investigated.The substituents were introduced via substituted 1,2-dibromopropanes, by cyclization with 3-thiapentane-1,5-dithiolate in the form of its molybdenum complex (2-).The functionalized macrocycles were then displaced from the metal by additional 3-thiapentane-1,5-dithiolate.A series of complexes (n+) (M = Ag, Hg, Cu, Ni, Co or Fe; L = 2-methyl-1,4,7-trithiacyclononane, the simplest of the new ligands) was prepared.Spectroscopic and electrochemical studies revealed that any effects of substitution on the ring conformational preferences were not manifested in the stability or electrochemistry of the complexes.Molecular-mechanics calculations suggest that no alterations in conformational preferences are caused by a single substitution.Attempts to synthesize analogues with two vicinal methyl groups yielded only polymeric products.
- Smith, Raymond J.,Salek, Spencer N.,Went, Michael J.,Blower, Philip J.,Barnard, Neil J.
-
p. 3165 - 3170
(2007/10/02)
-
- Synthesis of 2,4(5)-Bis(hydroxymethyl)imidazoles and 2,4(5)-Bisimidazoles: Precursors of 2,4(5)-Connected Imidazole Crown Ethers
-
Two syntheses of 1--2,4-bisimidazole, 3, a precursor to imidazole-containing crown ethers, are described.The first involved hydroxymethylation of 1-benzylimidazole with formaldehyde to afford 1-benzyl-2,5-bis(hydroxymethyl)imidazole (5) (20percent yield), which was elaborated into 3 in four steps.An alternative and more efficient route involved coupling of diamine 17b with the imino ether obtained from nitrile 11b to afford imidazoline 18b.The imidazoline was found to oxidize under Swern conditions, providing a mild new method of imidazole synthesis.Sulfamylation and debenzylation produced 3.This approach was also applied to the synthesis of 1--2,4-bis(hydroxymethyl)imidazole (2).Diol 3 was converted into 2,4-connected imidazole crown ethers, one of which (4) formed a crystalline complex with water.The complex structure was determined by X-ray crystallography.
- Zimmerman, Steven C.,Cramer, Katherine D.,Galan, Adam A.
-
p. 1256 - 1264
(2007/10/02)
-
- Novel heterocyclic derivatives bearing an amino radical, processes for their production and the pharmaceutical compositions containing them
-
This invention relates to novel heterocyclic derivatives bearing an amino group and to processes for making said compounds. More particularly this invention provides novel heterocyclic compounds the hetero ring of which has two hetero atoms, the same or different, substituted with a free or substituted amino group. These compounds are useful as active ingredients of drugs.
- -
-
-