4,4,5,5-tetramethyl-2-phenethyl-1,3,2-dioxaborolane

http://orgsyn.org/demo.aspx?prep=v94p0234

 4,4,5,5-Tetramethyl-2-phenethyl-1,3,2-dioxaborolane (1) has the following physical and spectroscopic properties: R_f = 0.47 (3:97, ethyl acetate:pentane), the checkers report the following values for 1: R_f = 0.09 (3:97 ethyl acetate:pentane); R_f = 0.52 (10% EtOAc in hexanes); Merck silica gel 60 F254 plate; mp 38-39 °C; 

¹H NMR pdf(CDCl₃, 400 MHz) δ: 1.18 (t, J = 8.4 Hz, 2H), 1.26 (s, 12H), 2.79 (t, J = 8.0 Hz, 2H), 7.16-7.22 (m, 1H), 7.23-7.32 (m, 4H); 

¹³C NMR pdf(CDCl₃, 151 MHz) d: 25.0, 30.1, 83.2, 125.6, 128.1, 128.3, 144.6 [N.B. the carbon attached to boron was not observed due to quadrupolar relaxation]; 

HRMS (ESI⁺) calculated for C₁₄H₂₂BO₂⁺ = 233.1707, mass found = 233.1710; 

IR (film): 3026, 2978, 2929, 1372, 1318, 1139, 848, 755, 703 cm^-1; 

Anal. calcd for C₁₄H₂₁BO₂: C, 72.44; H, 9.12. Found: C, 72.18; H, 9.28. 

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3,6−bis([1,1'−biphenyl]−4−ylmethyl)−1,2,4,5−tetrazine

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).

 

(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

tert-Butyl 3a,4,7,7a-Tetrahydro-1H-isoindole-2(3H)-carboxylate

tert-Butyl 3a,4,7,7a-Tetrahydro-1H-isoindole-2(3H)-carboxylate

    

tert-Butyl 3a,4,7,7a-Tetrahydro-1H-isoindole-2(3H)-carboxylate 

 as a brown oil. % Purity: 93.72% (GC);

 

¹H NMR (CDCl₃, 400 MHz) δ: 1.47 (s, 9H), 1.89–194 (m, 2H), 2.20–2.33 (m, 4H), 3.08 (dd, J₁ = 6.2 Hz, J₂= 10.2 Hz, 1H), 3.17 (dd, J₁ = 4.8 Hz, J₂ = 10.4 Hz, 1H), 3.37–3.43 (m, 2H), 5.65 (s, 2H);

 

¹³C NMR (CDCl₃, 100 MHz) δ: 24.63, 24.68, 28.49, 33.35, 34.23, 50.86, 50.92, 78.88, 124.19, 124.50, 155.22;

 

IR (CHCl₃): ν = 756, 1128, 1170, 1217, 1411, 1685, 2937, 2978, 3009 cm^–1;

 

TOFMS: [C₁₃H₂₁NO₂ + H⁺]: calculated 224.1645, found 168.0958 (M-tBu + H)⁺ (100%), 246.1382 (M + Na)⁺ (5%).

 

GC conditions were as follows for compound 4; Agilent GC-FID 7890A, column: ZB-5MSi (30 m X 0.32 mm, 0.25 µm) with injector temperature 250 ºC and detector temperature 280 ºC, diluent was Methanol, Oven temperature was at 70 ºC isocratic for 3 min. then raised up to 250 ºC @ 20 ºC/min then 15 min. hold.

 

 

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.6b00399

http://pubs.acs.org/doi/full/10.1021/acs.oprd.6b00399

////////

3,6−bis([1,1'−biphenyl]−4−ylmethyl)−1,2,4,5−tetra zine

3,6−bis([1,1'−biphenyl]−4−ylmethyl)−1,2,4,5−tetra zine

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.

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 tetrazines from gem-difluoroalkenes under aerobic conditions at room temperature

Zheng Fang,^a   Wen-Li Hu,^a   De-Yong Liu,^a  Chu-Yi Yu^ab and   Xiang-Guo Hu*^a  

Hide Affiliations

*

Corresponding authors

^a

National Engineering Research Center for Carbohydrate Synthesis, Jiangxi Normal University, Nanchang 330022, P. R. China
 E-mail: huxiangg@iccas.ac.cn

^b

Beijing 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

3,6−bis([1,1'−biphenyl]−4−ylmethyl)−1,2,4,5−tetra zine (3a). (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.



///////

2,3,4,4a,5,6-hexahydro-1H-pyrido[1,2-a]quinolone (R)-7

1H NMR (500 MHz, CDCl3): δ 7.82 (br s, 1H), 7.28-7.34 (m, 2H), 7.22-7.24 (m, 1H), 3.87 (m, 1H), 3.56 (m, 1H), 3.32 (m, 1H), 3.00-3.03 (m, 2H), 2.46-2.74 (m, 3H), 1.65-2.05 (m, 5H);

13C NMR (100 MHz, CDCl3): δ 137.6, 130.4, 129.2, 127.9, 124.1, 55.9, 54.5, 27.3, 25.2, 22.9, 20.3, 17.1;

Enantiomeric excess was determined by SFC: Chiralpak OD-3, 4.6 mm x 150 mm, particle size: 3 μm, temperature: 30 ºC, A: CO2, B: ethanol with 0.2% of isobutylamine, isocratic: A/B: 95/5, v/v, flow rate 3.0 mL/min.

HRMS (ESI) [M+H]+ m/z calcd for [C13H18N]+ is 188.1361 found 188.1429.

Synthesis of Enantioenriched 2‐Alkyl Piperidine Derivatives through
Asymmetric Reduction of Pyridinium Salts
Bo Qu,* Hari P. R. Mangunuru, Xudong Wei, Keith R. Fandrick, Jean-Nicolas Desrosiers, Joshua D.
Sieber, Dmitry Kurouski, Nizar Haddad, Lalith P. Samankumara, Heewon Lee, Jolaine Savoie, Shengli
Ma, Nelu Grinberg, Max Sarvestani, Nathan K. Yee, Jinhua J. Song and Chris H. Senanayake
Chemical Development, Boehringer Ingelheim Pharmaceuticals, Inc. 900 Ridgebury Road,
Ridgefield, CT 06877 USA
/////////////

4,6,7,8,9,10-hexahydro-1H-6,10-methanopyrazino[2,3-h][3]benzazepine-2,3-dione.

Chemical structures of Varenicline Tartrate and degradant product (DP-I).........4,6,7,8,9,10-hexahydro-1H-6,10-methanopyrazino[2,3-h][3]benzazepine-2,3-dione.

(A) ¹H NMR spectrum of DP-I. (B) Proton decoupled ¹³C NMR spectrum of DP-I.


UHPLC-ToF MS⁺ of DP-I.

The impurity obtained as pale white crystals. mp 71–73. 

RP-UHPLC, tR = 1.8 min (98.5% purity).

MS (ESI, 70 eV): [M + H⁺] m/z 244. 

FT-IR (KBr), v, cm⁻¹ 3371, 3319, 3279, 3173, 3005, 2808, 1696, 1678, 1588, 1406, 1388, 1338, 1305, 1264, 1135, 1067, 873, 790, 680, 569, 485.

¹H NMR (400 MHz, DMSO-d₆ +D₂O, TMS): δ 7.2 (s, 2H, H-7,8), 3.1–3.4 (m, 6H, H-11,13,14 & 16),2.3 (m, 1H, H-12), 2.0 (d, 1H, 11.2 Hz, H-12).

¹³C NMR (100 MHz, DMSO-d₆, TMS): δ 173.8 (C-2,3), 155.1 (C-5,6), 137.6 (C-9,10), 125.1 (C-7,8), 38.8 (C-11), 37.9 (C-12), 38.8 (C-13), 45.8 (C-14), 48.6 (C-16).

UHPLC ToF MS+: m/z [M + H⁺].Calcd for C₁₃H₁₃N₃O₂: 244.1086; found: 244.1082.

Based on the above spectral data, the molecular formula of DP-I is C₁₃H₁₃N₃O₂ and the corresponding structure was characterized as 4,6,7,8,9,10-hexahydro-1H-6,10-methanopyrazino[2,3-h][3]benzazepine-2,3-dione.

PMC full text:

Sci Pharm. 2012 Apr-Jun; 80(2): 329–336. Published online 2012 Mar 20. doi:  10.3797/scipharm.1201-08

http://dx.doi.org/10.3797/scipharm.1201-08

1,4,8,11-TETRATHIACYCLOTETRADECANE

.


 1,4,8,11-Tetrathiacyclotetradecane (24194-61-4)



 


1,4,8,11-tetrathiacyclotetradecane, mp 118–119°C (lit. ¹ mp 119–120°C)  

1. Rosen, W.; Busch, D. H. J. Am. Chem. Soc. 1969, 91, 4694.

The product 1,4,8,11-tetrathiacyclotetradecane shows the following spectral properties:

IR (KBr) cm⁻¹: 2930, 1430, 1338, 1270, 1205, 1138, 692;

 ¹H NMR (CDCl₃) δ: 1.90 (quintet, 4 H, J = 7, CCH₂), 2.65 (t, 8 H, J = 7, SCH₂CH₂), 2.77 (s, 8 H, SCH₂).

 

 3,7-dithianonane-1,9-diol, bp 200°C (1.5 mm)
  bp 179–181°C (0.5 mm).
: ¹H NMR (CDCl₃) δ: 1.86 (quintet, 2 H, J = 7, CCH₂), 2.17 (br s, 2 H, OH), 2.65 (t, 4 H, J = 7, SCH₂), 2.73 (t, 4 H, J = 6, SCH₂), 3.73 (t, 4 H, J = 6, OCH₂).
 
 3,7-dithianonane-1,9-dithiol, bp 159–162°C (1.2 mm)
  ¹H NMR (CDCl₃) δ: 1.63–2.07 (m, 4 H, CCH₂, SH), 2.50–2.83 (m, 12 H, SCH₂).

1,4,8,11-Tetrathiacyclotetradecane (24194-61-4)

3,7-Dithianonane-1,9-diol (16260-48-3)

3,7-Dithianonane-1,9-dithiol (25676-62-4)

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HELSINKI, FINLAND

Hi Everyone. Today's trip is to Helsinki, Finland. It's a new place
for me, I know nothing about it.

Helsinki is the capital and largest city of Finland. It is located in
southern Finland, on the shore of the Gulf of Finland, an arm of the
Baltic Sea. Helsinki has a population of 614,074 as of January 2014.

Helsinki is Finland's major political, educational, financial, cultural
and research center as well as one of northern Europe's major cities.
Approximately 70% of foreign companies operating in Finland have
settled in the Helsinki region.

In 2009, Helsinki was chosen to be the World Design Capital for 2012 by
the International Council of Societies of Industrial Design. In
2011, the Monocle Magazine ranked Helsinki the most livable city in
the world in its Livable Cities Index 2011.

Helsinki is spread across a number of bays and peninsulas and over a
number of islands. The inner city area occupies a southern peninsula.
Much of Helsinki outside the inner city area consists of postwar
suburbs separated from each other by patches of forest. A narrow, 6
mile long Helsinki Central Park that stretches from the inner city to
the northern border of Helsinki is an important recreational area
for residents.

Major islands in Helsinki include Seurasaari, Lauttasaari and Korkeasaari.
Other significant islands are the fortress island of Suomenlinna
(Sveaborg) and the military island of Santahamina. Finland's biggest
zoo is located in Korkeasaari.

February is normally the coldest month with average temperatures between
19 and 29 degrees Fahrenheit. July is normally the warmest month
with average temperatures between 58 and 71 degrees F. August tends
to be the rainiest month with an average of 3.15 inches, and a yearly
average of 25.79 inches of rain. February is normally the snowiest
month with an average of 9.4 inches, and a yearly average of 28.3
inches of snow.

I hope you enjoy this trip to Helsinki, Finland.

COAT OF ARMS

MAP

LUOTSIKATU IN KATAJANOKKA

STURENKATU

HELSINKI IN SUMMER

ALEKSANTERINKATU IN CENTRAL HELSINKI

WOODEN VALLILA (HOUSES)

ALEKSI IN CENTRAL HELSINKI (MARKET STREET)

HELSINKI LUTHERN CATHEDERAL
PROBABLY THE MOST PROMINENT BUILDING OF THE CITY


HELSINKI SQUARE

VIEW ACROSS ELAINTARHANLAHTI

PARLIAMENT OF FINLAND (ON THE RIGHT)
NEW SUPPLEMENTAL OFFICES (ON THE LEFT)


VIEW OVER THE SOUTHERNMOST DISTRICTS OF HELSINKI
THE HELSINKI OLD CHURCH AND ITS SURROUNDING PARK ARE SEEN IN THE FOREGROUND, THE TOWERS OF ST. JOHN'S CHURCH ARE NEAR CENTER, AND MIKAEL AGRICOLA CHURCH NEAR RIGHT, GULF OF FINLAND IN BACK

VIEW OF HELSINKI CENTRAL RAILWAY STATION AND ITS SURROUNDINGS

JOHANNES CHURCH
SUOMENLINNA AT NIGHT IN WINTER

KAMPPI CENTRAL AND ITS SURROUNDINGS

KAMPPI CENNTER (SHOPPING AND TRANSPORTATION COMPLEX)

HAAGA-HELIA UNIVERSITY OF APPLIED SCIENCES

KIASMA MUSEUM OF CONTEMPORARY ART
BUILT IN 1998, DESIGNED BY AMERICAN ARCHITECT STEVEN HOLL


FINNISH NATIONAL THEATRE (SPELLED EUROPEAN WAY)
AND ALEKSIS KIVI STATUE IN RAUTATIENTORI

HELSINKI OLYMPIC STADIUM (FROM 1952 SUMMER OLYMPICS)

TRAMS IN HELSINKI

HELSINKI METRO
BRIGHT ORANGE TRAINS IS THE WORLD'S NORTHERNMOST SUBWAY

MALMI AIRPORT, ONE OF THE OLDEST IN THE WORLD

CENTRAL RAILWAY STATION

STOCKMANN DEPARTMENT STORE
(ALONG THE ALEKSANTERINKATU'S CHRISTMAS STREET)

RESTAURANT VLTAVA (RIGHT)
SANOMATALO (IN BACKGROUND)

ROOFTOPS OF THE SOUTHERN INNER CITY DISTRICTS

THE USPENSKI ORTHODOX CATHEDRAL




NATIONAL MUSEUM
ALTAR OF THE TEMPPELIAUKIO CHURCH THAT IS BUILT UNDERGROUND

ITIS SHOPPING CENTRE (LARGE SHOPPING MALL IN THE EASTERN SUBURBS)

THE DISTRICT OF TOOLO

THE DESIGN MUSEUM

THE HOUSE OF ESTATES

INTERIOR OF OLD MARKET HALL KAUPPAHALLI

HUVILAKATU IN ULLANLINNA

SILTASAARI

SUVILAHTI

HELSINKI OBSERVATORY
BUSINESS CENTER
MORMON TEMPLE

MARKET BUILDING

MARKET SQUARE
CATHEDRAL SUNSET STREET ROAD

DOWN THE STREET

SIBELIUS MONUMENT

****************************************************************
UNIVERSITY OF HELSINKI
MAIN BUILDING

KAISATALO LIBRARY

****************************************************************
AERIAL VIEW






ALONG THE WATER










FORTRESS OF SUOMENLINNA


A LITTLE ISLAND

LOOKS LIKE A LIGHTHOUSE (?)
WOW!!!
THE ESPLANADI PARK IN EARLY JUNE

HIETANIEMI BEACH IN THE SUMMER

THE SOUTH HARBOR

KULOSAARI BRIDGE

WATER TOWER

OLD PHOTOS
EROTTAJA RESCUE STATION

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