13211-01-3Relevant articles and documents
Rh-Catalyzed Coupling of Aldehydes with Allylboronates Enables Facile Access to Ketones
Zhang, Kezhuo,Huang, Jiaxin,Zhao, Wanxiang
supporting information, (2022/02/21)
We present herein a novel strategy for the preparation of ketones from aldehydes and allylic boronic esters. This reaction involves the allylation of aldehydes with allylic boronic esters and the Rh-catalyzed chain-walking of homoallylic alcohols. The key to this successful development is the protodeboronation of alkenyl borylether intermediate via a tetravalent borate anion species in the presence of KHF2 and MeOH. This approach features mild reaction conditions, broad substrate scope, and excellent functional group tolerance. Mechanistic studies also supported that the tandem allylation and chain-walking process were involved.
Palladium-Catalyzed Carbonylative Coupling of Aryl Iodides with Alkyl Bromides: Efficient Synthesis of Alkyl Aryl Ketones
Peng, Jin-Bao,Chen, Bo,Qi, Xinxin,Ying, Jun,Wu, Xiao-Feng
supporting information, p. 4153 - 4160 (2018/09/21)
Alkyl aryl ketones are important structures with applications in many areas of chemistry. Hence, efficient procedures for their production are particularly attractive. In this communication, a general and efficient carbonylative cross-coupling of aryl iodides and unactivated alkyl bromides is presented. By using a simple palladium catalyst, a series of alkyl aryl ketones were synthesized in moderate to excellent yields from readily available alkyl and aryl halides in an In-Ex tube with formic acid as the CO source. In this study both primary and secondary alkyl bromides/iodides were suitable coupling partners. Additionally, this method can also be employed for the late-stage functionalization of complex natural products and polyfunctionalized molecules. (Figure presented.).
Benzylic carbon oxidation by an in situ formed o-iodoxybenzoic acid (IBX) derivative
Ojha, Lawanya R.,Kudugunti, Shashi,Maddukuri, Padma P.,Kommareddy, Amitha,Gunna, Meena R.,Dokuparthi, Praveen,Gottam, Hima B.,Botha, Kiran K.,Parapati, Divya R.,Vinod, Thottumkara K.
scheme or table, p. 117 - 121 (2009/05/30)
Benzylic C-H bonds are selectively oxidized to the corresponding carbonyl functionalities using catalytic quantities of 2-iodobenzoic acid (2IBAcid) and Oxone. The reported procedure tolerates different functional groups and operates under mild conditions. A radical mechanism is proposed for the transformation and evidence supporting the proposed mechanism is also presented. Georg Thieme Verlag Stuttgart.
Synthesis of thiophene/phenylene co-oligomers. V [1]. Functionalization at molecular terminals toward optoelectronic device applications
Katagiri, Toshifumi,Ota, Satoshi,Ohira, Takayuki,Yamao, Takeshi,Hotta, Shu
, p. 853 - 862 (2008/04/12)
(Chemical Equation Presented) We report the synthesis of various thiophene/phenylene co-oligomers with a total number of thiophene and benzene (phenylene) rings of 5 and 6 with various terminal groups. Those terminal groups have been chosen from among alkyl groups, methoxy groups, trifluoromethyl groups, and cyano groups. The molecular backbone of these compounds comprises phenyl- or biphenylyl-capped thiophene (or oligothiophene) or an alternating co-oligomer. The synthesis is based on either the Suzuki coupling reaction or the Negishi coupling reaction. These reaction schemes enabled us to obtain the target compounds in high quality. In particular, the latter coupling method turned out to produce the compounds at a high yield. The terminal groups are expected to produce various functionalities based upon their electron donating character (alkyl groups and methoxy groups) or electron withdrawing character (trifluoromethyl groups and cyano groups). Additionally some of these groups bring about enhanced solubility. This will lead to the production of a diversity of modified compounds of thiophene/phenylene co-oligomers. To give an example that demonstrates usefulness of the target compounds, we present optoelectronic data that are associated with their device applications.
5-Phenyl substituted 1-methyl-2-pyridones and 4′-substituted biphenyl-4-carboxylic acids. synthesis and evaluation as inhibitors of steroid-5α-reductase type 1 and 2
Picard, Franck,Schulz, Tobias,Hartmann, Rolf W.
, p. 437 - 448 (2007/10/03)
The synthesis of a series of 5-phenyl substituted 1-methyl-2-pyridones (I) and 4′-substituted biphenyl-4-carboxylic acids (II) as novel A-C ring steroidomimetic inhibitors of 5α-reductase (5αR) is described. Compounds 1-4 (I) were synthesized by palladium catalyzed cross coupling (Ishikura) reaction between diethyl(3-pyridyl)borane and aryl halides (1b-4b) followed by α-oxidation with sodium ferrocyanate of the 1-methyl-pyridinium salt. Inhibitors II (5-18) were obtained either by two successive Friedel-Crafts acylations from biphenyl (5a-10a) followed by saponification to yield the corresponding carboxylic acids (5-10) or by Suzuki cross coupling reaction to give the 4′-substituted biphenyl 1-4-carbaldehydes 11a-18a. The latter compounds were subjected to a Lindgren oxidation to yield compounds 11-18. The compounds were tested for inhibitory activity toward human and rat 5 αR1 and 2. The test compounds inhibited 5αR, showing a broad range of inhibitory potencies. The best compound in series I was the N-(dicyclohexyl)-4-(1,2-dihydro-1-methyl-2-oxopyrid-5-yl) benzamide 4 exhibiting an IC50 value for the human type 2 enzyme of 10 μM. In series II, the most active compound toward human type 2 isozyme was the 4′-(dicyclohexyl)acetyl-4-biphenyl carboxylic acid (10; IC50 = 220 nM). Both series showed only marginal activity toward the human type 1 isozyme. In conclusion, the biphenyl carboxylic acids (II) are more appropiate for 5αR inhibition than the 5-phenyl-1-methyl-2-pyridones (1). Especially the 4′-carbonyl compounds 5-10 represent new lead structures for the development of novel human type 2 inhibitors. Copyright
The Formation of Ketones by a Reaction Equivalent to R- + R'COCH2+ -> R'COCH2R
Katritzky, Alan R.,Wrobel, Leszek,Savage, G. Paul,Deyrup-Drewniak, Malgorzata
, p. 133 - 139 (2007/10/02)
A general method has been developed for the overall transformation of α-bromo ketones to α-alkyl or α-aryl ketones, with benzotriazole being used as a synthetic auxiliary, α-Benzotriazolyl ketones, when converted into their phenylhydrazones, reacted smoothly with alkyl and aryl Grignard reagents, which displaced benzotrazolate, to give the corresponding α-alkyl and α-aryl hydrazones.In some cases, these hydrolysed directly to the α-alkyl or α-aryl ketones.In each case, the product was treated with 2,4-dinitrophenylhydrazine to isolate the target ketones as the corresponding 2,4-dinitrophenylhydrazones.
SYNTHESIS OF 4-ALKYL-4'-CYANOBIPHENYLS
Ruolene, Yu. I.,Adomenas, P. V.,Sirutkaitis, R. A.,Denis, G. I.
, p. 1187 - 1191 (2007/10/02)
Liquid crystals of the 4-alkyl-4'-cyanobiphenyl group were synthesized without the use of copper cyanide. 4-Alkyl-4'-formylbiphenyls and the 4-formyloximes of 4'-alkylbiphenyl, which possess a liquid-crystalline state, were isolated.Beginning with the pentyl homolog, they form an enantiotropic nematic phase, and beginning with octyl homolog they also form a smectic meso phase.
