The preparation and photolysis of (E)-1-Aryl-3-methyl-3-phenylbut-1-enes

1983 ◽  
Vol 36 (3) ◽  
pp. 565 ◽  
Author(s):  
JW Blunt ◽  
JM Coxon ◽  
WT Robinson ◽  
HA Schuyt

Reaction of 2-methyl-2-phenylpropylmagnesium chloride with benzaldehyde in tetrahydrofuran gave 2,7-dimethyl-2,4,5,7-tetraphenyloctane-4,5-diol as a 1 : 2 mixture of clear transparent crystalline plates (meso) and needles (�), 3-methyl-1,3-diphenylbutan-1-one, benzyl alcohol, 2-methyl-2-phenylpropaneand a low yield of 3-methyl-1,3-diphenylbutan-1-ol. The distinction between the meso and the (+)- diols was unequivocal because the unique space group of the former requires thedimeric molecules to lie about a crystallographic centre of symmetry. The mechanism involved in the formation of the products of the Grignard reaction is examined. By careful choice of reaction conditions a series of I-aryl-3-methyl-3-phenylbutan-1-ols were prepared. Dehydration of the 1-aryl-3-methyl-3-phenylbutan-1-ols with p-toluene sulfonic acid and a short reaction time gives(E)-1-aryl-3-methyl-3-phenylbut-1-enes but longer reaction times afford 3-aryl-1,1-dimethylindanes.Photolysis of the (E)-1-aryl-3-methyl-3-phenylbut-1-enes affords (Z)-1-aryl-3-methyl-3-phenylbut-1-enes and trans-1-aryl-3,3-dimethyl-2-phenylcyclopropanes. Extended photolysis gives 4-aryl-2-methyl-3-phenylbut-1-enes via trans-1-aryl-3,3-dimethyl-2-phenylcyclopropane by rupture of the cyclopropyl bond adjacent to the aryl substituent.

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Xiao-chuan Jia ◽  
Jing Li ◽  
Yu Ding ◽  
Bin Zhang ◽  
Na Wang ◽  
...  

A robust, facile, and solvent-free route for the three-component synthesis of 2H-indazolo[2,1-b]phthalazine-triones in the presence of a catalytic amount ofp-toluene sulfonic acid utilizing grinding has been developed. Short reaction time, simple operation, and high yields are the advantages of this protocol.


2014 ◽  
Vol 900 ◽  
pp. 361-364
Author(s):  
Xiao Hui Wang ◽  
Xi Hua Du ◽  
Li Min Dong

Esters of Citric acid and palmityl alcohol were synthesized by esterification reaction under catalysis of cation exchange resin and P-toluene sulfonic acid respectively. The effects of amount of catalyst, ratio of raw materials, reaction time and temperature on the synthesis reaction were investigated . The experimental results showed that optimum of process conditions were 1:1~1:1.5 molar ratio of citric acid and palmityl alcohol, reaction temperature of 130~140°C, reaction time of 2 h. Conversion of palmityl alcohol were all more than 90% under 0.3% dosage using p-toluene sulfonic acid as the catalyst, or 0.5% dosage using 721 cation exchange resin with sulfonic acid type as catalyst. The synthesized product had good surface activity.


Synlett ◽  
2018 ◽  
Vol 29 (20) ◽  
pp. 2689-2692 ◽  
Author(s):  
Haifeng Wang ◽  
Xiangli Sun ◽  
Shuangling Zhang ◽  
Guanglu Liu ◽  
Chunjie Wang ◽  
...  

An efficient method for the synthesis of pyrazoles through a copper-catalyzed condensation reaction has been developed. The new catalytic system not only maintained a broad substrate scope but was also active under acid-free reaction conditions, overcoming the conventional requirement for an acid-catalyzed system. Furthermore, the copper catalyst enabled this reaction to be performed at room temperature and in a short reaction time.


2020 ◽  
Vol 22 (22) ◽  
pp. 7955-7961
Author(s):  
Wenjing Gao ◽  
Yameng Wan ◽  
Zhiguo Zhang ◽  
Hao Wu ◽  
Tongxin Liu ◽  
...  

An intramolecular Hofmann reaction leads to diverse photocatalytically active 6H-pyrido[1,2-c] quinazolin-6-one derivatives with the advantages of mild reaction conditions, short reaction time, excellent yields, broad substrate scope and high FG tolerance.


2019 ◽  
Vol 31 (4) ◽  
pp. 829-833
Author(s):  
D.S. Bhagat ◽  
S.G. Pande ◽  
M.V. Katariya ◽  
R.P. Pawar ◽  
P.S. Kendrekar

One-pot efficient protocol to the synthesis of 2-amino-5-oxo-4,5-dihydropyrano(3,2-c)chromene-3-carbonitrile derivatives via condensation of various aryl aldehydes, dicyanomethane and 4-hydroxycoumarin in presence of Emim hydroxide as an excellent homogeneous liquid catalyst. The key advantages of this methodology are mild reaction conditions, novel catalyst, short reaction time, eco-friendly, easy work-up procedure and high yield of isolation of derivatives.


2012 ◽  
Vol 90 (2) ◽  
pp. 167-172 ◽  
Author(s):  
Pranjal P. Bora ◽  
H. Atoholi Sema ◽  
Barisha Wahlang ◽  
Ghanashyam Bez

A catalytic amount (2 mol %) of phosphotungstic acid (PTA) is sufficient to synthesize homoallylic alcohol in excellent yields from aldehyde with allyltributylstannane upon grinding under solvent-free reaction conditions. Easy handling, very short reaction time, solvent-free reaction conditions, and aqueous workup free isolation protocol may make our method very useful for synthetic chemists.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maryam Kamalzare ◽  
Mohammad Reza Ahghari ◽  
Mohammad Bayat ◽  
Ali Maleki

AbstractRecently magnetic nanocatalyst has attracted considerable attention because of its unique properties, including high performance, easy separation from the reaction mixture, and recyclability. In this study, a novel magnetic bionanocomposite was synthesized with chitosan and tannic acid as a natural material. The synthesized bionanocatalyst was characterized by essential analysis. Fe3O4@chitosan-tannic acid as a heterogeneous nanocatalyst was successfully applied to synthesize pyranopyrazole and its derivatives by a one-pot four-component reaction of malononitrile, ethyl acetoacetate, hydrazine hydrate, and various aromatic aldehyde. At the end of the reaction, the nanocatalyst was separated from the reaction mixture and was reused several times with no significant decrease in its catalytic performance. Simple purification of products, the ability for recovering and reusing the nanocatalyst, eco-friendliness, high yields of pure products, mild reaction conditions, short reaction time, non-toxicity, economically affordable are some of the advantages of using the fabricated nanocatalyst in the synthesis of pyranopyrazole.


Author(s):  
Yahya Mirzaie ◽  
Jalil Lari ◽  
Hooshang Vahedi ◽  
Mohammad Hakimi ◽  
Ahmad Nakhaei ◽  
...  

Various potentials antibacterial fluoroquinolone compounds were prepared by the direct amination of 7-halo-6- fluoroquinolone-3-carboxylic acids with variety of piperazine derivatives and (4aR,7aR)-octahydro-1H-pyrrolo[3,4-b] pyridine using (NH<sub>4</sub>)<sub>42</sub> [Mo<sup>VI</sup><sub>72</sub>Mo<sup>V</sup><sub>60</sub>O<sub>372</sub>(CH<sub>3</sub>COO)<sub>30</sub>(H<sub>2</sub>O)<sub>72</sub>], a Keplerate-type giant-ball nanoporous isopolyoxomolybdate, as a catalyst in refluxing water. The results showed that this catalyst acts as effective catalyst and the reaction proceeded more easily and gave the highest yields of the products in short reaction time under refluxing water. Short reaction times, simple isolation of the products, and usage of eco-friendly catalysts are some features of this procedure. In addition, the catalysts was easily recovered and used in multiple catalytic cycles. This material was prepared according to a previously published literature procedure using inexpensive and readily available starting materials.


2021 ◽  
Vol 16 (9) ◽  
pp. 1934578X2110458
Author(s):  
Le Nhat Thuy Giang ◽  
Dang Thi Tuyet Anh ◽  
Hoang Thi Phuong ◽  
Nguyen Ha Thanh ◽  
Nguyen Thi Quynh Giang ◽  
...  

For the first time the 4-dimethylaminopyridine (DMAP) catalyzed straightforward and efficient procedure has been developed for the synthesis of 3,3′-(arylmethylene) bis(2-hydroxynaphthalene-1,4-dione) derivatives starting from lawsone (2-hydroxy-1,4-naphthoquinone) and a variety of (hetero)aromatic aldehydes in ethanol under microwave irradiation. Three of nine synthesized compounds are new. This method provides notable advantages over existing procedures including use of non-traditional basic catalyst and environmentally benign solvent, mild reaction conditions, excellent yields, short reaction time and simple workup.


2017 ◽  
Vol 41 (7) ◽  
pp. 380-383
Author(s):  
Maryam Salari ◽  
Alireza Hassanabadi ◽  
Mohammad H. Mosslemin

We report a green and efficient method for the synthesis of trans-[3-(aryl)-2,3-dihydrofuro[3,2- h]quinolin-2-yl]-(4-chlorophenyl) methanones from the condensation of 2-[2-(4-chlorophenyl)-2-oxoethyl)]isoquinolinium bromide with 8-hydroxyquinoline and an aromatic aldehyde in the presence of catalytic amounts of choline hydroxide in water at reflux conditions. This new protocol employing choline hydroxide, which is a green and inexpensive catalyst, offers advantages such as mild reaction conditions, short reaction time, high yields and does not involve any hazardous solvent. Therefore, this procedure can be classified as green chemistry.


Sign in / Sign up

Export Citation Format

Share Document