Ethyl(1R,2S,3S,4S)-2-(furan-2-yl)-3-nitro-6-oxobicyclo[2.2.2]octane-1-carboxylate

Ethyl(1R,2S,3S,4S)-2-(furan-2-yl)-3-nitro-6-oxobicyclo[2.2.2]octane-1-carboxylate

Compound 7 Ethyl(1R,2S,3S,4S)-2-(furan-2-yl)-3-nitro-6-oxobicyclo[2.2.2]octane-1-carboxylate To a solution of CAT 10 (128 mg, 0.37 mmol) and the nitroolefin 9 (3.1 g, 22.3 mmol) in 10 mL anhydrous CH2Cl2 at room temperature was added enone 8 (1.8 g, 10.7 mmol). The resulting mixture was stirred at the same temperature until enone 8 is consumed as indicated by TLC. Then DBU (0.34 mL, 3.20 mmol) was added and the mixture was allowed to stir at ambient temperature until completion as indicated by TLC. The solution was concentrated in vacuo and purified by flash chromatography on silica gel (Hexane / EtOAc = 20 / 1) to give 7 (2 g, 61% yield) as a yellow solid. [α]D 23 28.0 (c = 1.0, CHCl3).

1H NMR (400 MHz, CDCl3): δ 7.29 (d, J = 0.8 Hz, 1H), 6.27 (dd, J = 2.0 Hz, J = 3.2 Hz, 1H), 6.14 (d, J = 4.0 Hz, 1H), 4.93 (m, 1H), 4.57 (d, J = 4.4 Hz, 1H), 4.11 (m, 2H), 3.04-3.02 (m, 1H), 2.80-2.75 (m, 1H), 2.60- 2.54 (m, 1H), 2.33-2.29 (m, 1H), 1.88-1.72 (m, 2H), 1.33-1.23 (m, 1H), 1.21 (t, J = 7.2 Hz, 3H).

13C NMR (100 MHz, CDCl3): δ 204.1, 168.7, 151.8, 142.5, 110.5, 108.1, 88.3, 61.3, 56.3, 42.0, 40.8, 33.7, 26.9, 19.2, 13.8.

IR (thin film): 3435, 3141, 3120, 2996, 2959, 1715, 1653, 1621, 1557, 1505, 1473, 1443, 1408, 1371, 1336, 1301, 1336, 1301, 1270, 1236, 1142, 1120, 1083, 1062, 1074, 1045, 1045, 1011, 996, 960, 930, 892, 884, 867, 803, 753, 628, 600, 508, 436 cm-1 .

LRMS (ESI): 308.0 (M+H)+ , 330.0 (M+Na)+ .

HRMS (ESI): calcd for C15H18O6N (M+H) + : 308.1129. Found: 308.1130.

Melting point: 117-118 oC.

Concise asymmetric total synthesis of (−)-patchouli alcohol

 Author affiliations

Abstract

The asymmetric total synthesis of (−)-patchouli alcohol was accomplished in a concise manner. Key reactions include a highly diastereo- and enantioselective formal organocatalytic [4 + 2] cycloaddition reaction, a radical denitration reaction, and an oxidative carboxylation reaction. The formal synthesis of norpatchoulenol was achieved as well.

Graphical abstract: Concise asymmetric total synthesis of (−)-patchouli alcohol

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“ORG CHEM SELECT” CATERS TO EDUCATION GLOBALLY, No commercial exploits are done or advertisements added by me. This is a compilation for educational purposes only. P.S. : The views expressed are my personal and in no-way suggest the views of the professional body or the company that I represent

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Total CCl4 guest alignment in a quasiracemic clathrate closely related to Dianin’s compound

CrystEngComm, 2017, 19,5703-5706
DOI: 10.1039/C7CE01275F, Communication
Christopher S. Frampton, James H. Gall, David D. MacNicol
In the trigonal CCl4quasiracemic clathrate, space group R3, formed from host components S-(-)-Dianin’s compound, 4, and its (+)-2R,4R 2-nor methyl analogue, 2, the unprecedented complete ordering of a C-Cl bond of the guest with respect to the c-axial direction and the participation of an unexpected host conformation is reported for the first time.

Total CCl4 guest alignment in a quasiracemic clathrate closely related to Dianin’s compound

 Author affiliations

Abstract

Single crystal X-ray analysis at 100 K reveals that in the trigonal CCl4quasiracemic clathrate, space group R3, formed from host components S-(−)-Dianin’s compound and its (+)-2R,4R 2-nor methyl analogue there is an unprecedented complete ordering of a C–Cl bond of the guest with respect to the c-axial direction. In this clathrate and that formed from the (+)-2R,4R and (+)-2R,4S epimers the participation of an unexpected host conformation is reported for the first time.

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trans-2-(benzo[d][1,3]dioxol-5-yl)-2-methylcyclopropane-1-carbonitrile

trans-2-(benzo[d][1,3]dioxol-5-yl)-2-methylcyclopropane-1-carbonitrile

yellowish solid (53 mg, 66%);

m.p. = 72 °C;

1 H-NMR (600 MHz, CDCl3): δ = 6.77 – 6.71 (m, 3H), 5.94 (s, 2H), 1.63 – 1.59 (m, 4H), 1.50 (dd, J = 9.1, 5.0 Hz, 1H), 1.26 (t, J = 5.3 Hz, 1H);

13CNMR (151 MHz, CDCl3): δ = 147.80, 146.73, 136.69, 120.64, 120.23, 108.28, 108.17, 101.19, 28.75, 23.86, 21.40, 11.30;

HRMS (ESI): m/z calc. for [C12H11O2NK]: 240.0414, found 240.04204;

IR (KBr): νmax/cm-1 = 2972, 2897, 2231, 1490, 1457, 1434, 1349, 1226, 1080, 1033, 924, 869, 808, 728.

1H NMR PREDICT

13C NMR PREDICT

 Green Chem., 2017, Advance Article

DOI: 10.1039/C7GC00602K, Communication

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C[C@@]1([C@H](C#N)C1)C2=CC(OCO3)=C3C=C2

2-{[6-Chloro-3-methyl-2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl]methyl}-4-fluorobenzonitrile

2-{[6-Chloro-3-methyl-2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl]methyl}-4-fluorobenzonitrile (4)

white solid . Mp: 193–195 °C.
1H NMR (400 MHz, CDCl3) δ (ppm): 7.74–7.76(m, 1H), 7.14–7.17 (m, 1H), 6.95–6.97 (m, 1H), 6.05 (s, 1H), 5.51 (s, 2H), 3.40 (s, 3H).

Efficient synthesis of isoquinolines in water by a Pd-catalyzed tandem reaction of functionalized alkylnitriles with arylboronic acids

Efficient synthesis of isoquinolines in water by a Pd-catalyzed tandem reaction of functionalized alkylnitriles with arylboronic acids

Green Chem., 2017, Advance Article
DOI: 10.1039/C7GC00267J, Paper
Kun Hu, Linjun Qi, Shuling Yu, Tianxing Cheng, Xiaodong Wang, Zhaojun Li, Yuanzhi Xia, Jiuxi Chen, Huayue Wu
Pd-catalyzed tandem reaction of functionalized alkylnitriles with arylboronic acids for the synthesis of diverse isoquinolines in water.

Efficient synthesis of isoquinolines in water by a Pd-catalyzed tandem reaction of functionalized alkylnitriles with arylboronic acids

Kun Hu,a   Linjun Qi,a   Shuling Yu,a   Tianxing Cheng,a  Xiaodong Wang,a   Zhaojun Li,b   Yuanzhi Xia,a  Jiuxi Chen*a and   Huayue Wua  
*Corresponding authors
aCollege of Chemistry & Materials Engineering, Wenzhou University, Wenzhou 325035, China
E-mail: jiuxichen@wzu.edu.cn
bInstitute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture, Beijing, China
Green Chem., 2017, Advance Article

DOI: 10.1039/C7GC00267J, 

A palladium-catalyzed tandem reaction of 2-(cyanomethyl)benzonitriles or 2-(2-carbonylphenyl)acetonitriles with arylboronic acids in water has been developed for the first time. This reaction features good functional group tolerance and provides a new strategy for the synthesis of diverse isoquinolines under mild conditions. The use of water as the reaction medium makes the synthesis process environmentally benign. Preliminary mechanistic experiments indicate that the major reaction pathway involves carbopalladation of the C(sp3)–cyano group and subsequent intramolecular cyclization findings that were further supported by density functional theory (DFT) calculations.
Capture
STR1

1,3-Diphenylisoquinoline (3a). Pale-yellow solid (103.5 mg, 92%),

mp 78-79 oC (lit.24,  73-74.5 oC). 24 J. D. Tovar and T. M. Swager, J. Org. Chem., 1999, 64, 6499

1H NMR (500 MHz, CDCl3) δ 8.25-8.23 (m, 2H), 8.15-8.14 (m, 1H), 8.09 (s, 1H), 7.95-7.93 (m, 1H), 7.84-7.83 (m, 2H), 7.70-7.67 (m, 1H), 7.59-7.50 (m, 6H), 7.44-7.40 (m, 1H);

13C NMR (125 MHz, CDCl3) δ 160.5, 150.3, 140.1, 139.8, 138.0, 130.4, 130.2, 128.8, 128.7, 128.6, 128.4, 127.7, 127.6, 127.2, 127.0, 126.0, 115.8.

//////// isoquinoline, pd-catalyzed, arylboronic acids

Resolution of Thiele’s acid

Resolution of Thiele’s acid

Jun Chen,a XuXin Sun,a Allen G. Oliver,b Jeremy E. Wulffa

aDepartment of Chemistry, University of Victoria, P.O. Box 3065 STN CSC, Victoria, BC V8W 3V6, Canada.

bMolecular Structure Facility, Department of Chemistry and Biochemistry, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, IN 46556, USA.

Corresponding author: Jeremy E. Wulff (e-mail: ).

ABSTRACT

Thiele’s acid has been resolved for the first time by diastereomeric salt formation with brucine. Determination of absolute stereochemistry was accomplished by X-ray crystallography of the corresponding diester. We anticipate that access to optically resolved Thiele’s acid will stimulate its use in a diverse range of applications requiring chiral molecular clefts.

Canadian Journal of Chemistry, 2017, 95(3): 234-238, 10.1139/cjc-2016-0125

STR0.JPG

 

str1

(–)-Thiele’s ester 2a as a white solid (200 mg, 81%). Spectral data were consistent with the racemic compound that has been described previously in the literature.5 [α]D 25 = –216 deg mL dm-1 g-1 (c = 0.25, ethanol solution). MP = 87–89 °C.

CCDC 1469300 contains the supplementary crystallographic data for compound (–)-2a. These data are available from the Cambridge Crystallographic Data Centre.

 

Synthesis of tetrazines from gem-difluoroalkenes under aerobic conditions at room temperature

Synthesis of tetrazines from gem-difluoroalkenes under aerobic conditions at room temperature

Green Chem., 2017, Advance Article
DOI: 10.1039/C6GC03494B, Paper
Zheng Fang, Wen-Li Hu, De-Yong Liu, Chu-Yi Yu, Xiang-Guo Hu
A procedure for the synthesis of tetrazines from gem-difluoroalkenes under aerobic conditions has been developed.

Synthesis of tetrazines from gem-difluoroalkenes under aerobic conditions at room temperature

Zheng Fang,a   Wen-Li Hu,a   De-Yong Liu,a  Chu-Yi Yuab and   Xiang-Guo Hu*a  
*Corresponding authors
aNational Engineering Research Center for Carbohydrate Synthesis, Jiangxi Normal University, Nanchang 330022, P. R. China
E-mail: huxiangg@iccas.ac.cn
bBeijing National Laboratory for Molecular Science (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
Green Chem., 2017, Advance Article

DOI: 10.1039/C6GC03494B, http://pubs.rsc.org/en/Content/ArticleLanding/2017/GC/C6GC03494B?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

An efficient and green procedure for the synthesis of tetrazines has been developed based on an old chemistry reported by Carboni in 1958. Both symmetric and asymmetric 3,6-disubstituted 1,2,4,5-tetrazines can be obtained in moderate to high yields from the corresponding gem-difluoroalkenes under aerobic conditions at room temperature. This work represents a rare example that ambient air is utilized as an oxidant for the synthesis of tetrazines.
Synthesis of symmetric 3,6-dialkyl-1,2,4,5−tetrazine(3a−3h)
To a solution of 1,1−difluoroalkenes (1a, 50 mg, 0.27 mmol) in N,N-dimethylformide (DMF,5 mL) was added hydrazine (80%, 35 mg, 1.35 mmol). After stirring at room temperature for 4−6 hours, saturated ammonium chloride (20 mL) was added and the reaction mixture was extracted with dichloromethane (10 mL×3). The organic layer was combined, dried with anhydrous sodium sulfate. The solvent was concentrated and the crude product was dissolved in a suspension of Ethyl Acetate(5 mL) and 10% potassium carbonate solution(wt%, 5 mL) and stirred at room temperature for 24h under air atomerspere until the organic layer turned into amaranth obviously. The organic layer was collected, dried with anhydrous sodium sulfate. The crude product was purified by flash column chromatography[silica gel(#100–200), toluene] to afford the pure 1,2,4,5−tetrazines(3a−3h).
3,6−bis([1,1’−biphenyl]−4−ylmethyl)−1,2,4,5−tetra zine (3a).
str1
(41 mg, 83%).
purple solid; m.p. 200−202°C;
IR(KBr) nmax/cm−1 2924, 2850, 1488, 1451, 1432, 1388, 851, 750;
1 H NMR (400 MHz, CDCl3) 7.55−7.33 (m, 18H), 4.65 (s, 4H).
13C NMR (100 MHz, CDCl3) δ 169.2, 140.6, 140.4, 134.8, 129.7, 128.8, 127.6, 127.4, 127.1, 40.9;
HRMS (ESI): calcd. for C28H22N4 [M+H]+ 415.19172, found 415.19124.

///////tetrazines,  gem-difluoroalkenes, aerobic conditions, room temperature