A solvent-free catalytic protocol for the Achmatowicz rearrangement

Graphical abstract: A solvent-free catalytic protocol for the Achmatowicz rearrangement

Abstract

Reported here is the development of an environmentally friendly catalytic (KBr/oxone) and solvent-free protocol for the Achmatowicz rearrangement (AchR). Different from all previous methods is that the use of chromatographic alumina (Al2O3) allows AchR to proceed smoothly in the absence of any organic solvent and therefore considerably facilitates the subsequent workup and purification with minimal environmental impacts. Importantly, this protocol allows for scaling up (from milligram to gram), recycling of the Al2O3, and integrating with other reactions in a one-pot sequential manner.

A solvent-free catalytic protocol for the

Achmatowicz rearrangement

 Author affiliations

https://pubs.rsc.org/en/Content/ArticleLanding/2019/GC/C8GC03030H?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

1n: colorless oil, 0.33 g, 73% yield for 2 steps.

1H-NMR (400 MHz, DMSO) δ: 7.59–7.58 (m, 1H), 7.45 (s, 2H), 6.40 (dd, J = 3.2, 1.8 Hz, 1H), 6.29 (d, J = 3.2 Hz, 1H), 5.49 (s, 1H), 4.74–4.60 (m, 1H), 4.18–4.07 (m, 2H), 2.09–2.04 (m, 2H).

13C-NMR (100 MHz, DMSO) δ: 157.6, 142.4, 110.7, 106.1, 66.5, 62.8, 35.2. IR (KBr) 3282.9, 2928.7, 1627.4, 1562.5, 1353.8, 1174.6, 1074.0, 999.7, 918.4, 742.8 cm-1 ;

HRMS (CI+ ) (m/z) calcd. for C7H11NO5S [M]+ 221.0352; found 221.0354.

STR1 STR2 str3

2n (EtOAc/hexane = 3:1):colorless oil (dr 7:3), 46 mg, 97%.

1H-NMR (400 MHz, DMSO) δ: 7.48–7.47 (m, 2H), 7.34–7.02 (m, 2H), 6.12–6.03 (m, 1H), 5.61–5.48 (m, 1H), 4.60 (dd, J = 8.3, 4.1 Hz, 0.7H), 4.28 (ddd, J = 8.8, 4.0, 1.3 Hz, 0.3H), 4.20–4.11 (m, 2H), 2.27–2.20 (m, 1H), 1.97–1.86 (m, 1H).

13C-NMR (100 MHz, DMSO) δ: 196.7, 196.5, 151.9, 148.3, 127.7, 126.0, 90.9, 87.2, 74.6, 70.1, 65.8, 65.8, 30.3, 29.6. IR (KBr) 3370.4, 2987.0, 1689.5, 1364.3, 1268.0, 1178.4, 1023.3, 928.3, 755.1 cm-1 ;

HRMS (CI+ ) (m/z) calcd. for C7H11NO6S [M]+ 237.0302; found 237.0315.

STR1 STR2

////////////////Achmatowicz rearrangement

Advertisements

Synthesis of β-keto sulfones via a multicomponent reaction through sulfonylation and decarboxylation

Graphical abstract: Synthesis of β-keto sulfones via a multicomponent reaction through sulfonylation and decarboxylation

str1

1-Phenyl-2-(phenylsulfonyl)ethan-1-one (2a) 1

1H NMR (400 MHz, CDCl3) δ 7.92 (m, 4H), 7.70 – 7.58 (m, 2H), 7.54 (t, J = 7.6 Hz, 2H), 7.48 (t, J = 7.3 Hz, 2H), 4.74 (s, 2H).

13C NMR (101 MHz, CDCl3) δ 187.9, 138.7, 135.7, 134.4, 134.2, 129.3, 129.2, 128.9, 128.6, 63.4.

References 1. Lu, Q.; Zhang, J.; Peng, P.; Zhang, G.; Huang, Z.; Yi, H.; Millercd, T. J.; Lei, A. Chem. Sci. 2015, 6, 4851.

Synthesis of β-keto sulfones via a multicomponent reaction through sulfonylation and decarboxylation

*Corresponding authors

Abstract

A copper(I)-catalyzed synthesis of β-keto sulfones through a multicomponent reaction of aryldiazonium tetrafluoroborates, 3-arylpropiolic acids, sulfur dioxide, and water was developed. This reaction proceeds through a tandem radical process, and the sulfonyl radical, generated from the combination of aryldiazonium tetrafluoroborates with DABCO·(SO2)2, acts as the key intermediate. The transformation involves sulfonylation and decarboxylation, which allows for the efficient synthesis of the desired β-keto sulfones.

Graphical abstract: Synthesis of β-keto sulfones via a multicomponent reaction through sulfonylation and decarboxylation

Nickel-catalyzed carbonylation of arylboronic acids with DMF as a CO source

str1

Bis(4-methoxyphenyl)methanone

bis(4-methoxyphenyl)methanone (3b) The title product was purified by column chromatography and was obtained in 83% yield (110 mg). Rf = 0.3 (petroleum ether/ethyl acetate 30:1), light yellow oil.

1H NMR (400 MHz, CDCl3) δ (ppm):

7.80 (d, J = 8.8 Hz, 2H),  AROM H ORTHO TO -C=0

6.97 (d, J = 8.8 Hz, 2H),  AROM H ORTHO TO -OCH3

3.89 (s, 6H); TWO -OCH3 GPS

13C NMR (100 MHz, CDCl3) δ (ppm): 194.4, 162.9, 132.2, 132.1, 113.4, 55.5;

IR (KBr): 2957, 1671, 1593, 1260, 1093, 806 cm-1; HRMS(ESI) calc. for (M + Na+ ) 265.0844; found 265.0835.

Image result for MOM CAN TEACH YOU NMR

Image result for MOM CAN TEACH YOU NMR

MOM CAN TEACH YOU NMR

Nickel-catalyzed carbonylation of arylboronic acids with DMF as a CO source

Org. Chem. Front., 2017, 4,569-572
DOI: 10.1039/C7QO00001D, Research Article
Yang Li, Dong-Huai Tu, Bo Wang, Ju-You Lu, Yao-Yu Wang, Zhao-Tie Liu, Zhong-Wen Liu, Jian Lu
By using N,N-dimethylformamide (DMF) as a CO source, nickel-catalyzed carbonylation of arylboronic acids was demonstrated as an efficient and facile protocol for the synthesis of diaryl ketones.

Nickel-catalyzed carbonylation of arylboronic acids with DMF as a CO source

Abstract

By using N,N-dimethylformamide (DMF) as a CO source, the cheap metal nickel-catalyzed carbonylation of arylboronic acids was demonstrated as an efficient and facile protocol for the synthesis of diaryl ketones. Results indicated that NiBr2·diglyme was the best pre-catalyst among the investigated transitional metal salts, and excellent yields were achieved via C–H and C–N bond cleavage.

Graphical abstract: Nickel-catalyzed carbonylation of arylboronic acids with DMF as a CO source
Image result for MOM CAN TEACH YOU NMR
////////////http://www.rsc.org/suppdata/c7/qo/c7qo00001d/c7qo00001d1.pdf