155586-44-0Relevant academic research and scientific papers
New Intramolecular Five-Endo-Mode Cyclization of Allenyl Aryl Ketones
Nagao, Yoshimitsu,Lee, Woo-Song,Kim, Kweon
, p. 389 - 392 (1994)
A convenient preparation of allenyl aryl ketones was achieved by the Weinreb-modified Grignard reaction of N-methoxy-N-methylamides with propargylmagnesium bromide.On treatment with BF3*OEt2, the allenyl aryl ketones were converted to methylenebenzocyclopentenones via a new 5-endo-mode cyclization.
Room temperature Fe(NO3)3·9H 2O/TEMPO/NaCl-catalyzed aerobic oxidation of homopropargylic alcohols
Liu, Jinxian,Ma, Shengming
, p. 10161 - 10167 (2013/11/06)
A practical and eco-friendly aerobic oxidation of homopropargylic alcohols using Fe(NO3)3·9H2O/TEMPO/NaCl as catalysts at room temperature under atmospheric pressure was developed affording corresponding homopropargylic ke
InI3- or ZnI2-catalyzed reaction of hydroxylated 1,5-allenynes with thiols: A new access to 3,5-disubstituted toluene derivatives
Ma, Jie,Peng, Lingling,Zhang, Xiu,Zhang, Zhe,Campbell, Melody,Wang, Jianbo
, p. 2214 - 2220 (2011/06/19)
Transition-metal-activated alkynes or allenes can accept nucleophilic attack and undergo direct addition of the nucleophiles to the unsaturated bonds or trigger subsequent rearrangement reactions. This chemistry has witnessed increasing development in recent years. In this report, we have focused on the metal-catalyzed reactions of a variety of substituted propargyl allenic alcohols and thiophenols using indiumACHTUNGTRENUNG(III) and zinc(II) catalysts, which can activate both the alcohol and alkyne. In this reaction, thio groups play the role of a nucleophile and trigger subsequent rearrangements to give benzene derivatives. The products can be further transformed into various 1,3,5-trisubstituted aromatic compounds by nickel-catalyzed coupling reactions through the cleavage of the C-S bonds.
Synthesis of allenyl ketones and their palladium-catalyzed cycloisomerization/dimerization: Approaching the limits
Hashmi, A. Stephen K.,Choi, Ji-Hyun,Bats, Jan W.
, p. 342 - 357 (2007/10/03)
The preparation of several new allenyl ketones 1a-j and 1o-q is reported. In the case of allenyl ketones with nucleophilic groups in the side-chain like 1k-m, the material polymerized during the purification procedure; with the dialkyl thioether In the product of a Pummerer isomerization, the acetoxymethyl alkyl thioether, 11 was formed. Depending on the route to 1 sometimes either the acetate adducts 8 and the 1-propynyl ketones 9 or the dipropargyl and propargyl allenyl carbinol 14 and 15 were observed as side-products. Good yields of the sensitive aryl γ-halogen-allenyl ketones 23a and 23b were obtained by a new synthetic route, on the other hand the aryl γ-silylallenyl ketone 23c was readily desilylated. Subjecting the new allenyl ketones to the PdCl2(MeCN)2 catalyst provided the 2-substituted furans 2 and the 2,4-disubstituted furans 3 in most cases. The yields and ratios of these products strongly depended on the nature of the groups being present. With the aryl thioether and the γ-halogen allenyl ketones the palladium-catalyzed reaction failed. Detailed structural information about the new products was provided by the X-ray structure analyses of the p-acetamidophenyl propargyl carbinol 6g and the 2-aryl-4-(1-methyl-3-aryl-3-oxo-propen-1-yl furan 3h. Wiley-VCH Verlag GmbH, 1999.
Isomerizations on silica gel: Synthesis of allenyl ketones and the first Nazarov cyclizations of vinyl allenyl ketones
Stephen,Hashmi,Bats, Jan W.,Choi, Ji-Hyun,Schwarz, Lothar
, p. 7491 - 7494 (2007/10/03)
Dess-Martin oxidation followed by the chromatographic workup of crude, terminal propargyl ketones 5 on silica gel directly leads to terminal allenyl ketones 6. When the other substituent on 5 was electron-rich, 7 was observed as side-product. If the other substituent on 5 was electron-poor, the isomeric 1-propynyl ketone 8 was the side-product. Chromatography of the crude propargyl vinyl ketones 10 on silica gel delivers the products of a Nazarov cyclization.
