Скачиваний:
36
Добавлен:
15.08.2013
Размер:
190.1 Кб
Скачать

Supplement F2: The Chemistry of Amino, Nitroso, Nitro and Related Groups.

Edited by Saul Patai Copyright 1996 John Wiley & Sons, Ltd.

ISBN: 0-471-95171-4

CHAPTER 2

 

Structural chemistry

 

SALVATORE SORRISO

 

Dipartimento di Chimica, Laboratorio di Chimica Fisica, Universita` di Perugia,

 

06100 Perugia, Italy

 

Fax: 00 39 75 500 8851; e-mail: SORRISO@UNIPG.IT

 

I. LIST OF ABBREVIATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

85

II. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

85

III. THE AMINO GROUP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

86

 

A. Aliphatic Amines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

86

 

B. Alicyclic Amines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

88

 

C. Aromatic Amines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

90

 

D. Heterocyclic Amines and Related Molecules . . . . . . . . . . . . . . . . .

95

IV. THE NITROSO GROUP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

95

V. THE NITRO GROUP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

97

VI. CONCLUSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

101

VII. ACKNOWLEDGEMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

101

VIII. REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

102

 

I. LIST OF ABBREVIATIONS

 

ED

Electron diffraction

 

e.s.d. Estimated standard deviation; it is shown in parentheses and refers to the last

 

digits

 

G

Gas phase

 

ND

Neutron diffraction

 

RReliability index. The lower R, the more reliable are the results. R values ranging from 0.08 to 0.03 (8 and 3%, respectively) are usually obtained and it

 

is possible to go down to 0.02

S

Solid phase

XD

X-ray diffraction

II. INTRODUCTION

Period covered by the review: The present review constitutes an update and a continuation of the preceding one relating to the same functional groups1.

85

86

Salvatore Sorriso

Most papers published refer to quite complicated molecular frameworks and have as their only purpose determining the structure of the molecule itself as a whole; in fact, they do not pay particular attention to functional groups, which are the object of our work.

Since structural aspects of the present groups have been treated previously1, they will not be further examined unless they are new and interesting.

Techniques used in the research examined: In the period examined the most widely used technique was X-ray diffraction, even though neutron diffractometry has recently become popular.

The basic information indispensable to both these techniques may be found in the introduction to the previous reviews1,2. Further details may be found in Reference 3.

Units: Bond distances will be given in angstroms (A)˚ and bond angles in degrees (°).

III. THE AMINO GROUP

The compounds considered in this section have been subdivided, according to the molecular skeleton to which the amino group is attached, into four basic types: aliphatic, alicyclic, aromatic and heterocyclic.

A. Aliphatic Amines

The previous review1 has treated in detail only the following amines: methylamine, dimethylamine, trimethylamine, 2-aminoethanol, ethylenediamine, nitroguanidine and similar ones. In the period of the present review, some simple molecules of interest have been treated such as the aminoethanol series, including mono-, diand tri-substituted derivatives, as well as a number of derivatives of guanidine. These will be dealt with for purposes of internal comparison.

a. Aminoethanols. The structure of the monoethanolamine molecule (C2H7NO, MEAM) was previously studied using microwaves1. More recently, it has been determined once more using low-temperature single-crystal X-ray diffractometry (1)4 (R D 0.044), together with the related diethanolamine molecule (C4H11NO2, DEAM) (R D 0.030) and triethanolamine (C6H15NO3, TEAM) (R D 0.033).

The molecules of monoethanolamine (MEAN) are arranged in a three-dimensional grid. Rings of two N HÐ Ð ÐO bridged DEAM molecules are linked via strong O HÐ Ð ÐN bonds into one-dimensional tube-like stacks; weak N HÐ Ð ÐO bonds across the rings are also present. In the cases of DEAM and TEAM characteristic dimeric units are shown4. ‘All H atoms of the donor groups (i.e. the hydroxy, amino and imino groups) are involved in the hydrogen bonding system. Each molecule donates and accepts a total of six hydrogen bonds with mean strength increasing in the sequence MEAM, DEAM, TEAM. The length of the C O bonds is influenced by the number of strong hydrogen bonds (one or two) in which the respective O atom participates’4.

b. Guanidines. Studies have been made of the following molecules: 2-nitroguanidine (CH4N4O2), 2-cyanoguanidine (C2H4N4) and 1,2,3-triaminoguanidine (CH9N6).

The crystalline structure of 2-nitroguanidine had already been previously studied by Bryden and coworkers1 (Ref. 29 therein). They there report the existence, but not the position, of hydrogen bonds, which was instead rendered possible through the use of the neutron powder diffraction method5. The skeleton backbone of this molecule consisting of a central C atom and four N atoms is almost coplanar. Both nitramine groups are essentially on the plane of the molecular skeleton.

2. Structural chemistry

87

H(5)

O

H(11)

C(2)

C(1)

H(12)

H(21)

H(22)

H(3)

N

 

H(4)

(1)

Uncorrected values

N C(1)

 

1.449

(3)

O

 

1.418

(3)

C(2) ii

 

3.138

(3)

NÐ Ð ÐO

 

N H(3)

 

0.82

(5)

O H(5)

ii

1.04

(4)

H(4)Ð Ð ÐO

 

2.23

(2)

N C(1) C(2)i

114.2

(2)

N H(3)Ð Ð ÐOiii

149 (3)

O H(5)Ð Ð ÐN

147 (3)

C(1) iC(2)

1.518

(4)

NÐ Ð ÐOiii

2.785

(3)

OÐ Ð ÐN

3.282

(3)

N H(4) i

0.91

(2)

H(3)Ð Ð ÐOiii

2.05

(5)

H(5)Ð Ð ÐN

2.36

(4)

O

109.2 (2)

C(1) C(2) ii

175 (3)

N H(4)Ð Ð ÐO

For the 2-cyanoguanidine molecule6 the static deformation density has been mapped by least-square refinement against low-temperature X-ray data in order to explain the fact that the C N bonds around the C atom are almost identical and the fact that a large negative charge ( 0.2 e) is on the N(3) atom. Hence one must take all the resonance forms (2) into consideration.

In the 1,2,3-triaminoguanidine (CH8N6)7 one C N bond is particularly short (1.292 A)˚ while all other bond distances are comparable to the typical lengths of the C N and N N single bond distances. The structure consists of sheets of TAG oriented in the direction along the direction of the b axis and held together by molecular forces and hydrogen bonds.

In Table 1 we report structural parameters for some aliphatic amines.

88

 

Salvatore Sorriso

 

 

 

 

 

N(1)

 

 

 

 

 

 

 

 

 

 

 

H2N(5)

C

+

 

 

 

 

 

C

N(3)

 

 

 

 

 

 

H2N(6)

 

 

 

 

+

 

 

 

(a)

 

(b)

 

 

(c)

 

 

+

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

+

 

 

 

 

 

(d)

 

 

(e)

 

 

 

 

 

 

(2)

 

 

 

 

TABLE 1. Dimensions of the amino group in some aliphatic amines

 

 

 

 

 

 

 

 

 

 

Compound

C N

N H

<C N H

<H N H State

Method

Reference

Monoethanolamine

1.449(3)

0.82(5)

 

 

S

XD

4

 

 

0.91(2)

 

 

 

 

 

Diethanolamine

1.471(1)

0.88(1)

 

 

S

XD

4

Triethanolamine

1.467(1)

 

 

 

S

XD

4

2-Nitroguanidine

1.309(7)

0.96(2)

119.0(1)

125.0(1)

S

ND

5

 

 

0.98(2)

115.0(1)

 

 

 

 

 

1.330(8)

1.00(2)

121.0(1)

119.0(1)

 

 

 

 

 

0.96(2)

121.0(1)

 

 

 

 

2-Cyanoguanidine

1.334(8)a

1.00a

120.0(11)

119(2)

S

XD

6

 

 

1.00a

120.9(11)

 

 

 

 

 

1.343(8)a

0.98a

122.6(11)

116(2)

 

 

 

 

 

0.99a

120.6(11)

 

 

 

 

1,2,3-Triaminoguanidine 1.292(1)

 

 

 

S

XD

7

 

1.373(1)

 

 

 

 

 

 

 

1.381(1)

 

 

 

 

 

 

a Vibration corrected bond lengths based on the riding model for C(2) N(1), rigid body libration for other C N bonds, libration plus riding motion for N H bonds.

B. Alicyclic Amines

In the previous review1 this group of molecules was not taken into consideration.

a. 2,2,4,4,6-Pentacyanocyclohexenamine (C11H6N6)8. In this structure the presence of an olefinic bond constrains the molecule to assume a ‘half-chair’ conformation with the C(4) atom in the furthest position from the best plane. There is a conjugation involving the NH2 group and the olefin. So C NH2 [1.354(3)] bond distance is shorter than 1.475, which is typical in alifatic C N bond length and, at the same time, is at the upper end of the range [1.30(1) 1.33(1)] usually observed for olefine-amine derivatives. It is surprising that the group NH2 is twisted with respect to the molecular plane. For this molecule, in theory, two tautomers (3) may exist; X-ray measurements indicate the presence of only one tautomer (II) in the solid state.

 

2. Structural chemistry

89

CN

CN

CN

CN

NC

 

NC

 

H

 

 

 

 

 

 

NH

 

NH

NC

CN

NC

CN

 

I

(3)

II

 

 

 

b. N,N-Dimethyl-2-phenylcyclopropylamine hydrochloride (C11H16N)(4)9. This molecule is an inhibitor for an important class of enzymes, viz. the monoamino oxidases (MAO). Compounds of the type of trans-phenylcyclopropylamine ‘are drugs of steric interest as they contain the phenethylamine skeleton common to many neurotropic compounds, but with a rigid ethylamine side chain locked by cyclopropane ring’9.

C(4)

 

C(5)

 

 

C(10)

C(3)

 

C(6)

C(7)

C(9)

 

 

 

 

N

 

C(2)

 

C(1)

C(8)

 

C(11)

 

 

 

(4)

 

 

 

 

 

 

 

 

 

Uncorrected values

 

 

 

 

 

 

 

 

C(1) C(2)

1.43a

C(2) C(3)

1.32

C(3) C(4)

1.37

C(4) C(5)

1.39

C(5) C(6)

1.36

C(6) C(7)

1.43

1.36

1.36

1.51

C(7) C(8)

1.40

C(8) C(9)

1.35

C(9) N

1.49

1.51

1.461

1.48

C(10) N

1.50

C(11) N

1.51

 

1.40

1.49

1.49

 

 

 

1.50

 

1.46

 

 

C(1) C(2) C(3)

120

C(2) C(3) C(4)

120

C(3) C(4) C(5)

119

C(4) C(5) C(6)

124

C(5) C(6) C(1)

118

C(5) C(6) C(7)

118

125

115

123

C(6) C(7) C(8)

123

C(7) C(8) C(9)

119

C(8) C(9) N

121

125

59

115

 

124

 

62

 

119

C(9) N C(10) 110

C(10) N C(11) 111

 

 

 

111

 

110

 

 

a The upper and lower figures refer to the A and B molecules respectively.

Two independent molecules, A and B, are contained in each asymmetric unit, one being the mirror image of the other. The conformation of the two is not very different from that observed for molecules with a similar biological activity.

90

 

Salvatore Sorriso

 

 

 

 

TABLE 2. Structural parameters of the amino group in some alicyclic amines

 

 

 

 

 

 

 

 

 

 

Compound

C N

N H

<C N H

<H N H

State

Method

Reference

2,2,4,4,6-Pentacyano-

 

 

 

 

 

 

 

cyclohexenamine

1.354(3)

0.94(3)

122(2)

110(2)

S

XD

8

 

 

0.95(3)

127(2)

 

 

 

 

N,N-Dimethyl-2-

 

 

 

 

 

 

 

phenylcyclopropylamine

 

 

 

 

 

 

 

hydrochloridea

1.48

 

 

 

S

XD

9

 

1.40

 

 

 

 

 

 

1,2-trans-Diaminocyclo-

 

0.94(12)b

 

 

 

 

 

hexanehydrobromide

1.482(6)

 

 

S

XD

10

 

1.509(6)

 

 

 

 

 

 

 

1.487(6)

 

 

 

 

 

 

 

1.510(6)

 

 

 

 

 

 

1,4-trans-Diaminocyclo-

 

 

 

 

 

 

 

hexanedihydrochloride

1.494

 

 

 

S

XD

11

a There are two molecules in the asymmetric unit. b Average.

In Table 2 structural parameters of the amino group in some alicyclic compounds are reported in order to make a comparison. From this table one can see a clear difference in the C N bond distance between 2,2,4,4-pentacyanocyclohexenamine and some salts.

C.Aromatic Amines

a. 1,2-Diaminobenzene (C6H8N2) (5)12 R D 0.053 . The N(1) atom shows considerable deviation from the plane of the aromatic ring. In each NH2 group one of the two N H bonds is approximately coplanar with the ring. The lone pair of the nitrogen atom is situated on the opposite side as compared with the ring plane, such an orientation avoiding any repulsion between the lone pairs and overlap with the aromatic

electron system is possible. There is evidence that both N atoms are almost totally sp3- hybridized.

b. Hexaaminobenzene (C6H12N6) (6)13. The molecule has six identical CNH2 groups. The crystal packing is dominated by weak intermolecular NHÐ Ð ÐN interaction such that the nitrogen lone pair is positioned between adjacent hydrogens of nearby molecules. This results in an arrangement in which each molecule is surrounded by twelve other molecules in three different orientations.

Ab initio molecular orbital calculations have been carried out with the program GRADSCF. The results obtained for the D3d and S6 structures are compared with experimental data. Calculated C C and C N bond distances are in good agreement, unlike the N H lengths. The calculated geometry for NH2 groups is little different than that found experimentally.

In Table 3 structural parameters are presented for some characteristic aromatic amines.

c. o-Aminobenzoic acid (C7H7NO2). Two types of orthorhombic crystal of o- aminobenzoic acid exist under different conditions, that studied by Brown and Erhrenberg (anthranilic acid I, low-temperature form)18 and the other studied by Boone and coworkers (anthranilic acid II, higher-temperature form)19.

2. Structural chemistry

91

H(2)

H(11)

H(3)

C(2)

C(3)

C(4)

C(5)

H(4)

N(1)

H(12)

C(1)

C(6)

 

N(2)

H(21)

 

 

H(5)

 

 

 

H(22)

 

 

 

 

 

 

 

 

 

 

 

(5)

 

 

 

 

 

 

 

 

 

 

 

 

 

Uncorrected values

 

 

 

 

 

 

 

 

 

 

C(1) C(2)

1.385(2)

C(2) C(3)

1.388(2)

C(3) C(4)

1.381(2)

C(4) C(5)

1.381(2)

C(5) C(6)

1.390(2)

C(6) C(1)

1.407(2)

C(1) N(1)

1.406(2)

N H(11)

0.93(2)

N H(12)

0.93(2)

C(2) N(2)

 

C H

1.04

 

0.96(2)

N H(22)

0.97(2)

 

 

N(1) C(1) C(2)

122.3(2)

N(1) C(1) C(6)

118.6(2)

C(1) C(2) C(3)

121(2)

C(2) C(3) C(4)

119.8(2)

C(3) C(4) C(5)

119.8(2)

C(4) C(5) C(6)

121.1(2)

C(5) C(6) C(1)

1119.2(2)

C(6) C(1) C(2)

119.0(2)

N(2) C(6) C(5) 122.4(2)

C(6) N(2) H(22)

112.4(12)

C(1) N(1) H(11)

119.(12)

C(1) N(1) H(2)

115.9(12)

C(6) N(2) H(21)

110.3(12)

 

 

 

 

 

 

The low-temperature form I is stable up to 81 °C, above which temperature the structure changes to form II. Anthranilic acid I has 2 independent molecules for each asymmetric unit, one being neutral while the other has a zwitterionic form (C6H4NH3C COO ).

Anthranilic acid II possesses only non-zwitterionic molecules which form dimers of the A A type.

d.m-Aminobenzoic acid (C7H7NO3)20. has two independent molecules, A and B, both of them non-zwitterionic, forming dimers of the A B type.

e.p-Aminosalicylic acid (C7H5N5O)21. The data for p-aminosalicylic acid are in agreement with the idea that the resonance structures are determinant in explaining the structure of this molecule.

f.3,5-Diamino-2,4,6-trinitrobenzoic acid and related molecules24. Four similarlystructured molecules [containing the groups COOH (I), OH (II), F (III), C(DO)NH2 (IV),

92

Salvatore Sorriso

 

H(1)

N(1)

H(1)

C(1)

(6)

Uncorrected values

 

 

 

 

 

 

 

 

experimental

 

 

calculated

 

 

 

 

 

 

 

 

 

 

 

 

 

Da

Sa

Sb

N(1) C(1)

 

 

 

 

 

 

 

 

3d

6

6

 

 

 

 

1.432

(8)

1.457

1.459

1.426

N(1) H(1)

 

 

 

 

0.879

(56)

1.03

1.031

1.001

N(1)

 

H(1)0

 

 

 

 

0.841

(67)

1.03

1.032

1.004

 

c

 

 

 

 

1.383

(6)

1.396

1.395

1.392

C(1) C(1)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sb

C(1) N(1) H(1)

 

 

 

 

 

 

 

6

 

112

(4)

108.6

108.1

110.1

C(1)

 

N(1)

 

H(1)0

 

116

(5)

108.6

107.9

110.1

 

 

 

H(1)0

 

 

 

 

 

 

 

 

H(1)

 

N(1)

 

 

110

(5)

104.8

104.7

106.0

 

 

 

d

120

(1)

120.0

119.5

119.2

N(1) C(1) C(1)c

 

N(1)

 

C(1)

 

C(1)

 

120

(1)

120.0

120.5

120.8

 

 

 

 

 

 

 

 

 

 

 

 

C(1)

c

 

C(1)

 

C(1)

d

120.00

(2)

120.0

119.9

119.9

 

 

e

 

 

 

 

 

35.3

22.1, 48.2

10.9, 52.5

CC NH

 

 

 

 

 

 

 

a STO-3G.

b 6-31GŁ (N).

c 1/2-z, 1/2+x, y. d 1/2+y, z, 1/2-x. e Torsion angle.

 

 

2. Structural chemistry

 

 

93

TABLE 3. Dimensions of the amino group in some aromatic compounds

 

 

 

 

 

 

 

Compound

C N

N H

<C N H <H N H State Method Reference

1,2-Diaminobenzene

1.406(2)

0.93(2)

111.9(12)

113.0(17)

S

XD

12

 

 

0.93(2)

115.9(12)

 

 

 

 

 

1.408(2)

0.93(2)

110.3(1.2)

112.8(1.6)

 

 

 

 

 

0.97(2)

112.4(1.1)

 

 

 

 

Hexaaminobenzene

1.432(8)

0.879(56)

112(4)

110(5)

S

XD

13

 

1.429(7)a

0.841(67)

116(5)

 

 

 

 

2-Aminophenol

 

 

 

S

XD

14

2-Amino-4-

 

 

 

 

 

 

 

methylphenol

1.417(3)

 

 

 

S

XD

15

2-Amino-4-

1.433(9)a

 

 

 

 

 

 

chlorophenol

 

 

 

S

XD

14

2-Amino-5-nitrophenol

1.404(3)

0.85(4)

111(3)

108(4)

S

XD

16

o-Aminobenzoic acidb

 

0.97(5)

123(3)

 

 

 

 

1.364(5)

 

 

 

S

XD

17

o-Aminobenzoic acid

 

 

 

 

 

 

 

(anthranilic acid I)c

1.386(3)d

1.059(9)

111.6(6)

110.9(8)

S

ND

18

 

 

1.022(9)

110.4(5)

 

 

 

 

 

1.455(4)

1.039(8)

106.7(5)

113.8(7)

 

 

 

 

 

1.049(10)

113.0(6)

 

 

 

 

o-Aminobenzoic acid

 

 

 

 

 

 

 

(anthranilic acid II)

1.349(9)

0.84(4)

123.6(2.6)

 

S

XD

19

m-Aminobenzoic acidf

1.379(5)d

0.74(5)

117.1(3.7)

 

 

 

 

0.86(3)

119.9(2.1)

 

S

XD

20

 

1.395(5)e

0.91(3)

115.0(1.7)

 

 

 

 

 

0.92(3)

117.0(1.8)

 

 

 

 

 

 

0.91(3)

114.9(1.6)

 

 

 

 

p-Aminosalicylic acid

1.364(2)

0.91(3)

120(2)

125(2)

S

XD

21

 

 

0.83(3)

115(2)

 

 

 

 

5-Fluoro-2,4,6-trinitro-

 

 

 

 

 

 

 

1,3-benzenediamine

1.315(8)

1.06(9)

119(5)

120(9)

S

XD

22

 

 

1.0(2)

121(7)

 

 

 

 

 

1.320(9)

1.1(1)

117(8)

121(10)

 

 

 

 

 

1.0(1)

121(6)

 

 

 

 

3,5-Diamino-2,4,6-

 

 

 

 

 

 

 

trinitrophenol

1.320(7)

0.87(6)

120(4)

113(5)

S

XD

23

 

 

1.11(7)

119(4)

 

 

 

 

 

1.314(7)

0.88(7)

129(5)

109(7)

 

 

 

 

1.463(6)

0.78(7)

121(5)

 

 

 

 

3,5-Diamino-2,4,6-

 

 

 

 

 

 

 

trinitrobenzoic acid

1.321(3)

 

 

 

S

XD

24

o-Nitroanilinef

1.327(3)

 

 

 

 

 

 

1.371(18)d

 

 

 

 

 

 

( -form)

0.94(11)

113(7)

146(10)

S

XD

25

 

1.350(19)e

0.78(11)

101(8)

 

 

 

 

 

1.04(11)

126(6)

124(9)

 

 

 

 

 

0.89(11)

109(7)

 

 

 

 

2,4-Dinitroaniline

1.352

 

107.0

127.5

S

XD

26

 

 

 

125.2

 

 

 

 

2,6-Dinitroaniline

1.339(2)

 

 

 

S

XD

27

m-Cyanoaniline

1.408(7)

 

 

 

S

XD

28

p-Cyanoaniline

1.360(5)

 

 

 

S

XD

28

p-Chloroaniline

1.464(2)

 

 

 

S

XD

29

(continued overleaf )

94

 

Salvatore Sorriso

 

 

 

 

TABLE 3. (continued)

 

 

 

 

 

 

 

 

 

 

 

 

 

Compound

C N

N H

<C N H <H N H State

Method

Reference

2-Methyl-4-nitroaniline

1.353(3)

0.78(4)

126(2)

113(5)

S

XD

30

 

 

0.86(6)

121(4)

 

 

 

 

3-Chloro-4-fluoroaniline

1.398(2)

 

 

 

S

XD

31

a Corrected for molecular libration. b Monoclinic form.

c Low-temperature form; there are two molecules per asymmetric unit: one is neutral and the other a zwitterion. d Molecule A.

e Molecule B.

f There are two molecules per asymmetric unit.

TABLE 4. Relevant bond distances and angles in some heterocyclic amines

Compound

C N

N H

<C N H

<H N H

State

Method

Reference

5-Amino-1-H-

 

 

 

 

 

 

 

1,2,4-triazole

1.342

0.92

123

107

S

XD

32

 

 

0.89

126

 

S

XD

 

3-Amino-5-nitro-

 

 

 

 

 

 

 

1,2,4-triazole

1.342(2)

 

 

 

S

XD

33

1-Methyl-5-amino-

 

 

 

 

 

 

 

3-methylthio-

 

 

 

 

 

 

 

1,2,4-triazole

1.359(3)

 

 

 

S

XD

34

1-Phenyl-5-amino-

 

 

 

 

 

 

 

3-methylthio-

 

 

 

 

 

 

 

1,2,4-triazole

1.356(2)

 

 

 

S

XD

34

3,5-Diamino-1-H-

 

 

 

 

 

 

 

1,2,4-triazole

1.353(3)

0.89(2)

115(2)

115(2)

S

XD

32

 

 

0.86(2)

119(2)

 

 

 

 

 

1.376(3)

0.93(2)

114(1)

114(2)

 

 

 

 

 

0.83(2)

115(2)

 

 

 

 

5-Aminotetrazole

 

 

 

 

 

 

 

monohydrate

1.330(2)

0.87(2)

119(1)

119(2)

S

XD

35

 

 

0.88(2)

121(1)

 

 

 

 

2-Amino-1,3-oxazole

1.343(4)

0.91(5)

122(1)

 

S

XD

36

 

 

 

116(2)

 

 

 

 

2-Amino-1,3-thiazole

1.330(7)

0.83(4)

125(3)

113(5)

S

XD

37

 

 

0.76(4)

122(3)

 

 

 

 

2,5-Diamino-

 

 

 

 

 

 

 

1,3,4-thiadiazole

1.347(2)

 

 

 

S

XD

38

2,6-Diaminopyridinea

1.346(2)

 

 

 

 

 

 

1.377(4)

1.018(9)

116.3(5)

113.2(7)

S

ND

39

 

 

1.010(8)

115.9(5)

 

 

 

 

2,4,6-Triamino-

 

 

 

 

 

 

 

pyrimidineb

1.364(10)

 

 

 

S

XD

40

 

1.374(9)

 

 

 

 

 

 

 

1.371(9)

 

 

 

 

 

 

 

1.381(10)

 

 

 

 

 

 

 

1.376(9)

 

 

 

 

 

 

 

1.369(9)

 

 

 

 

 

 

2-Amino-6-

 

 

 

 

 

 

 

methoxypyrazine

1.344

0.89

120

122

S

XD

41

 

 

0.87

118

 

 

 

 

 

 

 

 

 

 

 

 

Соседние файлы в папке Patai S., Rappoport Z. 1996 The chemistry of functional groups. The chemistry of amino, nitroso, nitro and related groups