Molecular structure of diethylaminoalane in the solid state: an X-ray powder diffraction, DFT calculation and Raman spectroscopy study

The crystal structure of diethylaminoalane, [H₂Al—N(C₂H₅)₂]₂, was determined by X-ray powder diffraction in conjunction with DFT calculations. Diethyl­aminoalane crystallizes in the monoclinic space group P2₁/c with a = 7.4020 (2), b = 12.9663 (3), c = 7.2878 (2) Å and β = 90.660 (2)° at 293 K. The crystal structure was confirmed by DFT calculations and Raman spectroscopy. The molecular structure of diethylaminoalane consists of dimers of [H₂Al—N(CH₂CH₃)₂] in which an Al₂N₂ four-membered ring is formed by a center of inversion. Such an arrangement of the aminoalane moieties in the crystal structure is well known for this class of compound, as shown by the comparison with ethylmethyl­aminoalane and diisopropylaminoalane.

Computing details

Data collection: Stoe; program(s) used to solve structure: EXPO2009; program(s) used to refine structure: GSAS.

(AMAL_publ)

Crystal data

C4H12AlN	V = 699.41 (3) Å^3
Mr = 101.13	Z = 4
Monoclinic, P21/c	Dx = 0.960 Mg m^−3
a = 7.40203 (19) Å	Mo Kα1 radiation, λ = 0.7093 Å
b = 12.9663 (3) Å	T = 293 K
c = 7.28776 (17) Å	white
β = 90.660 (2)°

Data collection

Stoe StadiP diffractometer	2θmin = 2.966°, 2θmax = 60.071°, 2θstep = 0.015°
Scan method: step

Refinement

Least-squares matrix: full	74 parameters
Rp = 0.053	45 restraints
Rwp = 0.067	H atoms treated by a mixture of independent and constrained refinement
Rexp = 0.057	(Δ/σ)max = 0.08
R(F^2) = 0.28094	Background function: GSAS Background function number 1 with 20 terms.
3808 data points

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
N1	0.6344 (3)	0.9908 (2)	0.1284 (3)	0.0601 (14)*
C1	0.78016 (19)	0.91096 (11)	0.1319 (2)	0.0601 (14)*
C2	0.65640 (19)	1.06186 (11)	0.28800 (19)	0.0601 (14)*
C3	0.83310 (18)	1.12205 (11)	0.29266 (19)	0.0601 (14)*
C4	0.76494 (19)	0.84991 (11)	0.30853 (19)	0.0601 (14)*
Al1	0.3907 (3)	0.9387 (2)	0.1042 (4)	0.0849 (14)*
H1	0.285	0.972	0.262	0.0721 (17)*
H2	0.39331	0.8337	0.04098	0.0721 (17)*
H3	0.6492 (4)	1.0168 (2)	0.4114 (6)	0.0721 (17)*
H4	0.5449 (5)	1.1165 (3)	0.2865 (4)	0.0721 (17)*
H5	0.8594 (4)	1.1529 (2)	0.1581 (8)	0.0721 (17)*
H6	0.9437 (5)	1.0707 (3)	0.3340 (4)	0.0721 (17)*
H7	0.8230 (4)	1.1851 (3)	0.3909 (5)	0.0721 (17)*
H8	0.9115 (8)	0.9482 (2)	0.1264 (4)	0.0721 (17)*
H9	0.7637 (3)	0.8601 (3)	0.0163 (6)	0.0721 (17)*
H10	0.8284 (4)	0.7754 (4)	0.2917 (4)	0.0721 (17)*
H11	0.6213 (12)	0.8391 (2)	0.3417 (4)	0.0721 (17)*
H12	0.8328 (4)	0.8921 (2)	0.4207 (5)	0.0721 (17)*

Geometric parameters (Å, º)

N1—C1	1.495 (3)	Al1—N1	1.933 (4)
N1—C2	1.491 (3)	N1—C1	1.495 (3)
N1—Al1	1.932 (3)	N1—C2	1.491 (3)
N1—Al1	1.933 (4)	N1—Al1	1.932 (3)
C1—C4	1.516 (2)	C1—C4	1.516 (2)
C1—H8	1.086 (6)	C1—H8	1.086 (6)
C1—H9	1.076 (4)	C1—H9	1.076 (4)
C2—C3	1.523 (2)	C2—C3	1.523 (2)
C2—H3	1.075 (4)	C2—H3	1.075 (4)
C2—H4	1.088 (4)	C2—H4	1.088 (4)
C3—H5	1.079 (6)	C3—H5	1.079 (6)
C3—H6	1.095 (4)	C3—H6	1.095 (4)
C3—H7	1.090 (4)	C3—H7	1.090 (4)
C4—H10	1.082 (5)	C4—H10	1.082 (5)
C4—H11	1.102 (9)	C4—H11	1.102 (9)
C4—H12	1.100 (4)	C4—H12	1.100 (4)
Al1—H1	1.464	Al1—H1	1.464
Al1—H2	1.437	Al1—H2	1.437
C1—N1—C2	110.0 (2)	Al1—N1—Al1	90.3 (1)
C1—N1—Al1	115.6 (2)	C1—N1—C2	110.0 (2)
C2—N1—Al1	112.4 (2)	C1—N1—Al1	115.6 (2)
Al1—N1—Al1	90.3 (1)	C2—N1—Al1	112.4 (2)
N1—C1—C4	108.4 (1)	N1—C1—C4	108.4 (1)
N1—C1—H8	109.7 (2)	N1—C1—H8	109.7 (2)
N1—C1—H9	109.6 (2)	N1—C1—H9	109.6 (2)
C4—C1—H8	109.8 (2)	C4—C1—H8	109.8 (2)
C4—C1—H9	109.6 (2)	C4—C1—H9	109.6 (2)
H8—C1—H9	109.7 (3)	H8—C1—H9	109.7 (3)
N1—C2—C3	114.8 (1)	N1—C2—C3	114.8 (1)
N1—C2—H3	108.1 (2)	N1—C2—H3	108.1 (2)
N1—C2—H4	108.6 (2)	N1—C2—H4	108.6 (2)
C3—C2—H3	108.1 (2)	C3—C2—H3	108.1 (2)
C3—C2—H4	108.5 (2)	C3—C2—H4	108.5 (2)
H3—C2—H4	108.5 (3)	H3—C2—H4	108.5 (3)
C2—C3—H5	109.5 (2)	C2—C3—H5	109.5 (2)
C2—C3—H6	109.5 (2)	C2—C3—H6	109.5 (2)
C2—C3—H7	109.5 (2)	C2—C3—H7	109.5 (2)
H5—C3—H6	109.5 (3)	H5—C3—H6	109.5 (3)
H5—C3—H7	109.5 (3)	H5—C3—H7	109.5 (3)
H6—C3—H7	109.4 (3)	H6—C3—H7	109.4 (3)
C1—C4—H10	109.5 (2)	C1—C4—H10	109.5 (2)
C1—C4—H11	109.5 (3)	C1—C4—H11	109.5 (3)
C1—C4—H12	109.5 (2)	C1—C4—H12	109.5 (2)
H10—C4—H11	109.5 (3)	H10—C4—H11	109.5 (3)
H10—C4—H12	109.5 (3)	H10—C4—H12	109.5 (3)
H11—C4—H12	109.5 (3)	H11—C4—H12	109.5 (3)
N1—Al1—H1	109.4	N1—Al1—N1	89.7 (1)
N1—Al1—H2	110.2	N1—Al1—H1	120.1
N1—Al1—N1	89.7 (1)	N1—Al1—H2	99.7
H1—Al1—H2	122.7	N1—Al1—H1	109.4
H1—Al1—N1	120.1	N1—Al1—H2	110.2
H2—Al1—N1	99.7	H1—Al1—H2	122.7