Thermolysis of [(η5-C5H5) Co(PPh3)(η2-DMAD)], revisited: A solid state analysis reveals the true structure of the triphenylphosphine-alkyne coupling product

DOI: 10.1016/S0022-328X(02)02122-8

Source and publish data:

Journal of Organometallic Chemistry p. 1 - 7 (2003)

Update date:2022-07-29

Topics:

Authors:

O'Connor, Joseph M.

Bunker, Kevin D.

Read Full Text PDF DownLoad Join now for total 90,000,000 free articles

Article abstract of DOI:10.1016/S0022-328X(02)02122-8

Thermolysis of the η²-alkyne complex (η⁵-C₅H₅)Co(PPh₃) [η²-(MeO₂C)C=C(CO₂Me)] (1-DMAD) leads to formation of an ortho-metalated vinyl-phosphonium derivative (η⁵-C₅H₅) Co[η²-(MeO₂C)HC=C(CO₂Me) PPh₂(η¹-o-C₆H₄)] (4) as well as a small amount of the tricobalt bis(carbyne) cluster [(η⁵-C₅H₅)Co]₃ [μ³,η³-C(CO₂Me)]₂ (3-CO₂Me). Thermolysis of 1-DMAD in the presence of added triphenylphosphine gives 4 as the major product, with no evidence for formation of 3-CO₂Me. Complexes 4 and 3-CO₂Me were characterized by X-ray crystallographic analyses.

Full text of DOI:10.1016/S0022-328X(02)02122-8

Journal of Organometallic Chemistry 671 (2003) 1Á7

www.elsevier.com/locate/jorganchem

Short communication

Thermolysis of [(h⁵-C₅H₅)Co(PPh₃)(h²-DMAD)], revisited: a solid

state analysis reveals the true structure of the triphenylphosphineÁ

alkyne coupling product

Joseph M. O’Connor *, Kevin D. Bunker

Department of Chemistry and Biochemistry, 9500 Gilman Drive, University of California at San Diego, La Jolla, San Diego, CA 92093-0358, USA

Received 1 October 2002; received in revised form 19 November 2002; accepted 20 November 2002

Abstract

Thermolysis of the h²-alkyne complex (h⁵-C₅H₅)Co(PPh₃)[h²-(MeO₂C)CÄ

C(CO₂Me)] (1-DMAD) leads to formation of an

ortho-metalated vinyl-phosphonium derivative (h⁵-C₅H₅)Co[h²-(MeO₂C)HCÄ

C(CO₂Me)PPh₂(h¹-o-C₆H₄)] (4) as well as a small

amount of the tricobalt bis(carbyne) cluster [(h⁵-C₅H₅)Co]₃[m³,h³-C(CO₂Me)]₂(3-CO₂Me). Thermolysis of 1-DMAD in the

presence of added triphenylphosphine gives 4 as the major product, with no evidence for formation of 3-CO₂Me. Complexes 4 and

3-CO₂Me were characterized by X-ray crystallographic analyses.

Keywords: CobaltÁ

alkyne; Vinyl-phosphonium; Ortho-metalation; CarbonÃhydrogen bond activation

1. Introduction

An important approach toward carbonÁ

bond activation and functionalization is the hydroaryla-

CO₂Me; Scheme 1), with no observable alkyne insertion

products [2,4]. It was suggested that the unique reactiv-

ity observed for 1-DMAD was due to the presence of

two strong electron-withdrawing groups on the alkyne

ligand.

hydrogen

tion of triple bonds, wherein an alkyne inserts into a

Here we report the true structure of 2 to be the ortho-

metalated vinyl-phosphonium derivative 4, as revealed

by an X-ray crystallographic analysis. Structural char-

acterization of the bis(carbyne) cluster [(h⁵-

C₅H₅)Co]₃[m³,h³-C(CO₂Me)₂] (3-CO₂Me) is also re-

ported.

phenyl carbonÁhydrogen bond. [1] One of the earliest

examples of cobalt-mediated hydroarylation was a 1979

report on the thermal conversion of (h⁵-

C₅H₅)Co(PPh₃)[h²-C(CO₂Me)Ä

/C(CO₂Me)] (1-DMAD)

to an alkyne insertion product which was proposed to

have structure 2 (22% yield; Scheme 1) [2,3]. The

structural assignment for 2 was consistent with the

observation of resonances in the ¹H-NMR (CDCl₃)

2. Results and discussion

spectrum at d 2.05 (d, Jꢀ

(s, 3H), 4.60 (s, 5H), and 6.5Á

13 Hz, 1H), 3.45 (s, 3H), 3.68

8.5 (phenyl hydrogens);

Mononuclear cobaltÁalkyne complexes of the general

and fragment ion peaks in the mass spectrum corre-

sponding to C₂₃H₁₈O₃P and C₂₂H₁₈O₂P. In most cases,

the thermal decomposition of (h⁵-C₅H₅)Co(PPh₃)[h²-

type (h⁵-C₅H₅)Co(PPh₃)(h²-alkyne) (1) are useful pre-

cursors for the synthesis of metallaiminocyclobutenes

[5], metallacyclopentenes [6], alkene complexes [7], diene

complexes [8], cyclobutadiene complexes [9], metallacy-

clopentene complexes [10], metallacyclopentadiene com-

plexes [11], and a variety of products stemming from

(R¹CÅ

CR²)] (1) led to the formation of tricobalt

bis(carbyne) clusters [(h⁶-C₅H₅)Co]₃[m³,h³-CR¹][m³,h³-

CR²] (3, R¹or R²Ä

TMS, Ph, CN, Me, CÅCTMS,

[2ꢁ

studies on the use of cobaltÁ

precursors to metallacyclobutenes [13], we observed that

2ꢁ

2] cyclization reactions [12]. During the course of

alkyne complexes, 1, as

* Corresponding author. Tel.:

8585345383.

ꢁ

1-8585345836; fax:

ꢁ/1-

doi:10.1016/S0022-328X(02)02122-8

J.M. O’Connor, K.D. Bunker / Journal of Organometallic Chemistry 671 (2003) 1Á7

Scheme 1.

(h⁵-C₅H₅)Co(PPh₃)[h²-(CO₂Me)CÅ

/C(CO₂Me)]

(1-

was carried out in the presence of a large excess of PPh₃

the formation of 3-CO₂Me was not observed.

An X-ray crystallographic analysis (Fig. 1, Tables 1

and 2) of 4 revealed that ortho-metalation of the

triphenylphosphine ligand had indeed occurred, but

that a phosphorus and hydrogen had added across the

DMAD) underwent a slow thermal decomposition to

a new complex, 4, which was confirmed by NMR

spectroscopy to be identical to the compound previously

assigned structure 2. After heating a benzene-d₆solution

of 1-DMAD, containing 0.5 equivalents of PPh₃, at

alkyne triple bond to give a zwitterionic vinylÁphos-

60 8C for 27 days, a H-NMR spectrum of the sample

indicated the presence of 34% 1-DMAD, 43% of 4, and

6.5% of bis(carbyne) 3-CO₂Me. When a similar reaction

phonium complex, rather than the originally proposed

alkyne hydroarylation product. The five-membered

Fig. 1. An ORTEP view of vinylÁphosphonium complex (4) (50% probability thermal ellipsoids). Hydrogen atoms are omitted for clarity.

J.M. O’Connor, K.D. Bunker / Journal of Organometallic Chemistry 671 (2003) 1Á

Table 1

Selected bond lengths and angles for (4)

Bond lengths (A)

Distance

C(7)

C(2)

C(3)

C(8)

C(9)

C(10)

C(11)

C(12)

C(7)

C(3)

1.9318 (16)

1.9605 (16)

1.9984 (16)

1.412 (2)

1.397 (2)

1.386 (2)

1.392 (2)

1.389 (2)

1.414 (2)

1.461 (2)

C(2)

C(3)

C(1)

C(4)

C(8)

C(13)

C(19)

C(2)

C(1)

C(4)

O(1)

O(2)

O(3)

O(4)

P(1)

1.510(2)

1.467(2)

1.199 (2)

1.347 (2)

1.214 (2)

1.355 (2)

1.7692 (16)

1.8011 (16)

1.8003 (16)

1.7707 (16)

C(7)

C(8)

C(9)

C(10)

C(11)

C(12)

C(2)

Bond angles (8)

Angle

92.03(7)

Angle

69.73 (9)

66.97 (9)

C(7)

C(2)

C(8)

C(3)

C(2)

C(3)

C(2)

C(13)

C(19)

C(1)

P(1)

C(3)

C(2)

C(8)

C(7)

C(2)

C(3)

C(2)

C(3)

C(7)

C(8)

C(3)

C(1)

C(4)

88.01 (7)

43.30 (6)

102.94 (7)

110.50 (7)

110.74 (7)

120.98 (14)

117.76 (11)

117.28 (11)

110.59 (11)

119.08 (14)

127.18 (16)

127.40 (16)

P(1)

C(2)

P(1)

C(4)

O(1)

O(3)

metallacycle ring consisting of CoÃ

is puckered, with a pronounced fold angle of 36.68

between the CoÃC(7)ÃC(8)ÃP, and CoÃC(2)ÃP mean

C(7)Ã

C(8)Ã

PÃ

C(2)

planes. The deviations of C(2) and C(3) from the mean

plane defined by CoÃC(7)ÃC(8)ÃP are ꢂ0.68 and ꢂ

1.80 A, respectively. The alkene bonding to cobalt in 4 is

unsymmetrical with cobaltÁcarbon distances of

Table 2

Crystal data and structure reﬁnement for (4) and (3-CO₂Me)

1.9605(16) A and 1.9984(16) A for CoÃ

C(3), respectively.

A related arylÁ

C(2) and CoÃ

alkene complex, (h⁵-C₅H₅)Co(h²-

Compound

(4)

(3-CO₂Me)

C₂₁H₂₁Co₃O₄

514.17

Molecular formula

Molecular weight

Color

₂₉H₂₆CoO₄P

CH₂CH₂)[C₆H₅MgBr (tmeda)] (5), was previously char-

528.40

red

purple

Crystal system

Space group

Temperature (K)

monoclinic

P2(1)/n

150(2)

9.5920(14)

14.558(2)

17.362(3)

monoclinic

C2/c

100(2)

a (A)

15.440(2)

9.2788(12)

14.8018(19)

b (A)

c (A)

a (8)

b (8)

g (8)

V (A )

93.871(2)

115.818(2)

2419.0(6)

1.451

1908.9(4)

1.789

D_calc(cm m^ꢂ3

)

Absorption, coeffi-

cient, (mm^ꢂ1

Crystal size (cm³)

0.810

2.601

)

0.40ꢃ

0.71073

Reflections collected 20 683

0.24ꢃ

0.14

0.19ꢃ

0.71073

7989

0.15ꢃ0.08

Wavelength (A)

Refinement method

Full-matrix least-

squares on F²

5550/348

Full-matrix least-

squares on F²

2184/179

Data/parameters

Goodness-of-fit

Final R indices

1.057

1.087

R₁ꢀ

0.0810

R₁ꢀ0.0382, wR₂ꢀ

0.0842

/0.0319, wR₂ꢀ

R₁ꢀ

0.0511

R₁ꢀ0.0213, wR₂ꢀ

0.0518

/0.0200, wR₂ꢀ

Fig. 2. Solid state structure of (5) with the atom numbering scheme

from Ref. [14]. Selected bond lengths (A) and angles (8): CoÃ

C(6) 2.01,

C(8) 2.572; C(6)Ã

C(8) 93.58, MgÃCoÃC(8)

Co 67.85.

R indices (all data)

CoÃ

C(7) 1.434, C(6)Ã

67.41, C(6)ÃC(7)Ã

C(7) 1.981, CoÃ

CoÃ

Co 70.03; C(7)Ã

C(8) 1.977, CoÃ

C(8) 95.21, C(7)Ã

C(6)Ã

Mg 2.565, MgÃ

CoÃ

J.M. O’Connor, K.D. Bunker / Journal of Organometallic Chemistry 671 (2003) 1Á7

acterized by X-ray crystallography (Fig. 2) [14]. In the

case of 5, the magnesium atom is within bonding

distance to both cobalt and C(8) of the phenyl ligand.

which a reductive elimination of the hydride and vinyl

ligands would give 4.

A vinyligous analogue of 4 is the dienylÁphosphoni-

um complex 10, formed from reaction of ruthenium

cation 11 and two equivalents of alkyne (Scheme 4). The

proposed mechanism for the formation of 10 involves an

intramolecular migration of PPh₃from ruthenium to the

alkyne-derived metallacyclopentatriene a-carbon, fol-

lowed by ortho-metalation of the PPh₃substituent and

hydride migration to the carbene ligand [18].

By comparison the cobaltÁphosphorus non-bonded

distance in 4 is 2.930(3) A. The cobaltÁ

aryl bond

C(7), in 4 is 0.04 A shorter than the

corresponding distance, CoÃC(8), in 5. The C(2)ÃC(3)

alkene distance of 1.461(2) A in 4 is significantly longer

than the C(6)ÃC(7) double bond distance in 5, as

expected for a greater degree of p-backbonding.

VinylÁphosphonium complexes have been previously

prepared from ortho-metalation reactions of allylÁ

phosphonium salts. For example, reaction of

PtCl₂(NCPh)₂and [Ph₃PCH₂CHÄCH₂]Cl in 2-methox-

yethanol at reflux (22 h) leads to a 61% yield of the

distance, CoÃ

Finally, in addition to vinylÁphosphonium complex

4, thermolysis of 1-DMAD led to the isolation of a small

amount of crystalline [(h⁵-C₅H₅)Co]₃[m³,h³-C(CO₂Me)]₂

(3-CO₂Me; Scheme 2). Complex 3-CO₂Me was pre-

viously prepared in 16% yield from the high temperature

reaction of (h⁵-C₅H₅)Co(CO)₂and DMAD [4b]. Tri-

nuclear bis(carbyne) clusters are of interest as substrates

for the study of surface-homogeneous cluster analogies

[4b] and as building blocks for new materials [19]. We

therefore determined the solid state structure of 3-

CO₂Me (Fig. 4, Table 2) and provide bond length and

angle data in the caption for Fig. 4 and in the

supplementary material.

vinylÁphosphonium complex 6 (Scheme 3) [15]. In the

¹H-NMR spectrum of 6 (CD₂Cl₂) the vinyl hydrogen

resonance at d 4.56 exhibits a coupling constant ³J_{P H}

ꢀ

17.1 Hz. For 4 the related cis phosphorusÁ

hydrogen

coupling constant is J_{P H}

ꢀ

13 Hz [2]. The platinumÁ

alkene bond lengths in 6 are similar within experimental

error.

The formation of 4 from 1-DMAD involves the

breaking of carbonÁ

bonds, and the formation of cobaltÁ

phosphorus and carbonÁhydrogen bonds; making the

hydrogen and cobaltÁ

phosphorus

carbon, carbonÁ

3. Experimental

mechanism of formation a complex process. Triphenyl-

phosphine is known to react with DMAD to give the

reactive zwitterion, [Ph₃P^ꢁC(CO₂Me)Ä

CÄ

C(O^ꢂ)-

3.1. Conversion of (1-DMAD) to (3-CO₂Me) and (4)

(OMe)] (7, Fig. 3) [16]. Thus, alkyne dissociation

followed by reaction with PPh₃could generate 7,

followed by reaction at cobalt to give intermediate 8.

At least two reasonable mechanisms with no alkyne

dissociation are also possible. Intermediate 8 could form

by either an intramolecular migration of PPh₃from

cobalt to the coordinated alkyne, or via an intermole-

cular attack of PPh₃at the alkyne ligand. Ortho-

metalation [17] from 8 to give a cobalt(III) hydride

complex and reductive elimination would then generate

4. Alternatively, a mechanism involving cyclopentadie-

nyl ring-slippage followed by ortho-metalation of the

PPh₃ligand to give intermediate 9 is a possibility.

Migration of phosphorus from cobalt to the alkyne

ligand in 9 would lead to a vinyl hydride complex from

In a sealed NMR tube under a nitrogen atmosphere, a

benzene-d₆solution (0.51 ml) of (1-DMAD) (12.2 mg,

0.023 mmol, 0.046 M), PPh₃(30.3 mg, 0.116 mmol,

0.226 M) and toluene (as internal standard) was heated

at 60 8C. After 53 d, analysis of the sample by ¹H-NMR

spectroscopy indicated a 70% yield of vinylÁphospho-

nium complex (4) and the presence of 16% starting

material (1-DMAD). There was no evidence of bis(car-

byne) cluster (3-CO₂Me). In a separate experiment, an

NMR tube containing 1-DMAD and 0.53 equivalents of

PPh₃was heated for 27 d at 60 8C. A ¹H-NMR spectrum

of the sample indicated 39.5% starting material along

with 30% of (4) and 6.1% of bis(carbyne) cluster (3-

CO₂Me). The reaction temperature was then maintained

at 100 8C for 7 d resulting in 28% 1-DMAD, 50% 4, and

Scheme 2.

J.M. O’Connor, K.D. Bunker / Journal of Organometallic Chemistry 671 (2003) 1Á

Scheme 3.

J_{P C}

9.1 Hz), 178.0 (d, J_{P C}

ꢀ

ꢀ/10.9 Hz), 186.7 (d,

J_{P C}

ꢀ/25.0 Hz).

3.2. X-ray structure determination of (h⁵-C₅H₅)Co(h²-

(MeO₂C)HCÄ

C(CO₂Me)PPh₂(h¹-o-C₆H₄)] (4)

A single crystal with dimensions 0.40ꢃ

0.24ꢃ0.14

mm³was immersed in paratone and placed on a glass

fiber. Data was collected on a Bruker ^SMART(APEX)

CCD diffractometer by using graphite monochromator

with MoÁ

K_aradiation (lꢀ0.71073 A) at 150 K. The

structure was solved by direct methods and refined by

full-matrix least-squares on F². Atom H3 (the hydrogen

atom on C3) was refined, but all other hydrogen atoms

were geometrically fixed on their attached atoms [20].

Table 2 summarizes the crystal data collection and

refinement parameters.

Scheme 4.

4% 3-CO₂Me. Further heating of the sample led to slow

decomposition of the identified products.

In a preparative scale experiment 1-DMAD (0.153 g,

0.290 mmol) and PPh₃(0.758 g, 2.89 mmol) were heated

in dry benzene (ca. 5 ml) at 60 8C. After 40 d the

volatiles were removed in vacuo and the crude mixture

3.3. X-ray structure determination of bis(carbyne)

cluster [(h⁵-C₅H₅)Co]₃[m³,h³-C(CO₂Me)]₂(3-

CO₂Me)

subjected to chromatography (silica gel, 10Á30% ethyl

acetate/hexanes) in the air to give 4 (0.069 g, 45% yield)

as air-stable dark orange crystals. X-ray quality crystals

were grown by slow evaporation of the benzene solvent.

A single crystal with dimensions 0.19ꢃ

0.15ꢃ0.08

mm³was immersed in paratone and placed on a glass

fiber. Data was collected on a Bruker ^SMART(APEX)

¹H-NMR (C₆D₆): d 2.55 (d, 1H, J_{P H}

ꢀ13.8 Hz), 3.32

CCD diffractometer by using graphite monochromator

(s, 3H), 3.56 (s, 3H), 4.89 (s, 5H), 6.64 (m, 3H), 6.83Á

with MoÁ

K_aradiation (lꢀ0.71073 A) at 100 K. The

7.13 (m, 6H), 7.64 (m, 4H), 8.10 (m, 1H). ¹³C{¹H} NMR

structure was solved by direct methods and refined by

full-matrix least-squares on F². All hydrogen atoms were

geometrically fixed on their attached atoms during the

refinement. Equivalent atoms were generated by the

(C₆D₆): d 36.6, 50.8, 51.7, 85.6, 122.0 (d, J_{P C}

ꢀ13.5

Hz), 124.9, 125.3 (d, J_{P C}

ꢀ4.3 Hz), 126.0, 127.9, 128.3

(d, J_{P C}

14.7 Hz), 128.8 (d, J_{P C}

ꢀ

ꢀ10.9 Hz), 130.9 (d,

J_{P C}

19.5 Hz), 131.5, 132.2 (d, J_{P C}

ꢀ

ꢀ/3.0 Hz), 132.5,

symmetry transformation ꢂ

xꢁ

2, y, ꢂ

zꢁ1/2 [20].

132.7 (d, J_{P C}

2.5 Hz), 133.6 (d, J_{P C}

ꢀ

9.2 Hz), 134.5

Table 2 summarizes the crystal data collection and

refinement parameters.

(d, J_{P C}

9.2 Hz), 144.2 (d, J_{P C}

ꢀ

ꢀ17.6 Hz), 172.6 (d,

Fig. 3. Mechanistic considerations for the formation of 4 from 1-DMAD.

J.M. O’Connor, K.D. Bunker / Journal of Organometallic Chemistry 671 (2003) 1Á7

[4] (a) J.R. Fritch, K.P.C. Vollhardt, M.R. Thompson, V.W. Day, J.

Am. Chem. Soc. 101 (1979) 2768;

(b) J.R. Fritch, K.P.C. Vollhardt, Angew. Chem. Int. Ed. Engl. 19

(1980) 559;

5 (1986) 394;

(d) H. Wadepohl, S. Gebert, Coord. Chem. Rev. 143 (1995) 535;

For related routes toward analogues of 3

[5] (a) H. Yamazaki, K. Aoki, Y. Yamamoto, Y. Wakatsuki, J. Am.

Chem. Soc. 97 (1975) 3546;

(b) Y. Wakatsuki, S. Miya, S. Ikuta, H. Yamazaki, J. Chem. Soc.

Chem. Commun. (1985) 35;

Dalton Trans. (1986) 1201;

(d) Y. Wakatsuki, S. Miya, H. Yamazaki, J. Chem. Soc. Dalton

Trans. (1986) 1207.

[6] (a) Y. Wakatsuki, H. Yoshimura, H. Yamazaki, J. Organomet.

Chem. 366 (1989) 215;

(b) Y. Wakatsuki, K. Aoki, H. Yamazaki, J. Am. Chem. Soc. 96

(1974) 5284;

Fig. 4. An ORTEP view of bis(carbyne) cluster (3-CO₂Me) (50%

(1979) 1123.

probability thermal ellipsoids). Hydrogen atoms are omitted for

clarity. Selected bond lengths (A) and angles (8): Co(1)ÃCo(2)

[7] H. Yamazaki, N. Hagihara, J. Organomet. Chem. 21 (1970) 431.

[8] (a) P. Hong, K. Aoki, H. Yamazaki, J. Organomet. Chem. 150

(1978) 279;

2.3785(4), Co(1)Ã

C(1A) 1.8558(14), Co(2)Ã

C(1A)ÃCo(1)ÃC(1) 84.59(7), C(1A)Ã

Co(1)ÃCo(2) 59.664(7), C(1A)ÃCo(1)Ã

Co(2) 50.40(4), C(1A)ÃCo(1)ÃCo(1A) 49.88(4), C(1)Ã

49.62(4), Co(1A)ÃC(1)ÃCo(1) 80.50(6), Co(1A)ÃC(1)ÃCo(2) 79.47(6),

Co(1)ÃC(1)ÃCo(2) 79.29(6).

Co(1A) 2.4027(4), Co(1)Ã

C(1) 1.8652 (14), Co(2)Ã

Co(2)ÃC(1) 84.26(9), Co(1A)Ã

Co(2) 50.44(4), C(1)ÃCo(1)Ã

Co(1)ÃCo(1A)

C(1) 1.8628(14), Co(1)Ã

C(1A) 1.8652(14);

(b) Y. Wakatsuki, H. Yamazaki, J. Organomet. Chem. 149 (1978)

385;

Guzei, Organometallics 16 (1997) 5589;

(d) J.M. O’Connor, M.-C. Chen, A.L. Rheingold, Tetrahedron

Lett. 38 (1997) 5241.

[9] K. Yasufuku, H. Yamazaki, J. Organomet. Chem. 121 (1976) 405.

[10] Y. Wakatsuki, H. Yoshimura, H. Yamazaki, J. Organomet.

Chem. 366 (1989) 215

4. Supplementary material

Products guided by the article

Product name:[(η5-C5H5)Co(eta.2-(CO2Me)HC=C(CO2Me)PPh2(η1-o-C6H4))]

Cas No:565214-89-3

R&D Labs maybe for 565214-89-3

SICHUAN TONGSHENG AMINOACID CO.LTD

website:http://www.aminoacid.cc

Contact:86-838-2274206/2850606

Address:Room 1-11-1,No.19 of North TianShan Road,Deyang,Sichuan China
jintan yufan Medicine Raw materials Co.,Ltd.(expird)

Contact:86-519-82808282

Address:6th,Jincheng Huangzhuang
Jiangsu Hualun Chemical Industry Co., Ltd

website:http://www.hualunchem.com

Contact:+86-0514-86464168 86507985

Address:39# Middle Renmin Road, Dinghuo Town
Yicheng Goto Pharmaceuticals Co.,Ltd.

Contact:+86 710 3423122

Address:5th Floor,East Gate of Building #2,Servo-Industrial Park,1st Qilin Road,Xiangyang,Hubei,China
Hefei EnliPharma Tecnology Co.,Ltd

Contact:0086-551-66399836

Address:Qing Cheng ShuiXiang Building 805, Mengcheng North Road , ShuangFeng Economic Development Zone Anhui HeFei

Relevant to this article

Doi:10.1021/ja01861a069
(1940)
Doi:10.1016/S0040-4039(00)75272-5
(1975)
Doi:10.1139/v75-301
(1975)
Doi:10.1016/0040-4039(75)80052-9
(1975)
Doi:10.1007/BF00497312
()
Doi:10.1016/0040-4020(75)85095-2
(1975)

Article Doi

Thermolysis of [(η5-C5H5) Co(PPh3)(η2-DMAD)], revisited: A solid state analysis reveals the true structure of the triphenylphosphine-alkyne coupling product

DOI: 10.1016/S0022-328X(02)02122-8

Source and publish data:

Authors:

Article abstract of DOI:10.1016/S0022-328X(02)02122-8

Full text of DOI:10.1016/S0022-328X(02)02122-8

Products guided by the article

R&D Labs maybe for 565214-89-3

Relevant to this article

Hot Product