Comparison of the mechanisms of the thermal decompositions of 2,2′-azisobutane and azoisopropane

Gordon McKay; James M.C. Turner; Farhad Zaré

doi:10.1039/F19777300803

Comparison of the mechanisms of the thermal decompositions of 2,2′-azisobutane and azoisopropane

Gordon McKay
, James M.C. Turner^*
, Farhad Zaré

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

10 Citations (Scopus)

Abstract

The gas phase pyrolyses of 2,2′-azoisobutane and azoisopropane have been investigated in the temperature range 471-573 K. The products of 2,2′-azoisobutane (AIB) decomposition result from the following elementary reactions. AIB ^k1→ 2t-C₄H₉ + N₂ (1) 2t-C₄H₉ ^kd→ iC₄H₁₀ + iC₄H₈ (2) 2t-C₄H₄ ^kc→ 2,2,3,3-tetramethylbutane (3) The disproportionation-combination rate constant ratio, k_d/k_c, for t-butyl radicals has been determined as 2.60 ± 0.04 in the temperature range 483 to 515 K. In addition to the corresponding reactions (1) to (3) involving isopropyl radicals, azoisopropane (AIP) decomposition involves the abstraction reaction, iC₃H₇ + AIP ^ka→ C₃H₈ + AIP·. (4) In the temperature range, 518-573 K, k_a is given by the expression, log₁₀ k_a/(k_c)^1/2/cm^3/2 mol^-1/2 s^-1/2 = 5.26 ± 0.22 - (41.64 ± 2.31) kJ mol^-1/2.303 RT and the disproportionation-combination rate constant ratio for isopropyl radicals has been found to fall from 0.52 at 518 K to 0.49 at 573 K.

Original language	English
Pages (from-to)	803-816
Number of pages	14
Journal	Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases
Volume	73
DOIs	https://doi.org/10.1039/F19777300803
Publication status	Published - 1977
Externally published	Yes

Access to Document

10.1039/F19777300803

Cite this

@article{485ab577bb2e4ce488976e1fecc0bd93,

title = "Comparison of the mechanisms of the thermal decompositions of 2,2′-azisobutane and azoisopropane",

abstract = "The gas phase pyrolyses of 2,2′-azoisobutane and azoisopropane have been investigated in the temperature range 471-573 K. The products of 2,2′-azoisobutane (AIB) decomposition result from the following elementary reactions. AIB k1→ 2t-C4H9 + N2 (1) 2t-C4H9 kd→ iC4H10 + iC4H8 (2) 2t-C4H4 kc→ 2,2,3,3-tetramethylbutane (3) The disproportionation-combination rate constant ratio, kd/kc, for t-butyl radicals has been determined as 2.60 ± 0.04 in the temperature range 483 to 515 K. In addition to the corresponding reactions (1) to (3) involving isopropyl radicals, azoisopropane (AIP) decomposition involves the abstraction reaction, iC3H7 + AIP ka→ C3H8 + AIP·. (4) In the temperature range, 518-573 K, ka is given by the expression, log10 ka/(kc)1/2/cm3/2 mol-1/2 s-1/2 = 5.26 ± 0.22 - (41.64 ± 2.31) kJ mol-1/2.303 RT and the disproportionation-combination rate constant ratio for isopropyl radicals has been found to fall from 0.52 at 518 K to 0.49 at 573 K.",

author = "Gordon McKay and Turner, \{James M.C.\} and Farhad Zar{\'e}",

year = "1977",

doi = "10.1039/F19777300803",

language = "English",

volume = "73",

pages = "803--816",

journal = "Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases",

issn = "0300-9599",

publisher = "Faraday Division of the Chemical Society",

}

TY - JOUR

T1 - Comparison of the mechanisms of the thermal decompositions of 2,2′-azisobutane and azoisopropane

AU - McKay, Gordon

AU - Turner, James M.C.

AU - Zaré, Farhad

PY - 1977

Y1 - 1977

N2 - The gas phase pyrolyses of 2,2′-azoisobutane and azoisopropane have been investigated in the temperature range 471-573 K. The products of 2,2′-azoisobutane (AIB) decomposition result from the following elementary reactions. AIB k1→ 2t-C4H9 + N2 (1) 2t-C4H9 kd→ iC4H10 + iC4H8 (2) 2t-C4H4 kc→ 2,2,3,3-tetramethylbutane (3) The disproportionation-combination rate constant ratio, kd/kc, for t-butyl radicals has been determined as 2.60 ± 0.04 in the temperature range 483 to 515 K. In addition to the corresponding reactions (1) to (3) involving isopropyl radicals, azoisopropane (AIP) decomposition involves the abstraction reaction, iC3H7 + AIP ka→ C3H8 + AIP·. (4) In the temperature range, 518-573 K, ka is given by the expression, log10 ka/(kc)1/2/cm3/2 mol-1/2 s-1/2 = 5.26 ± 0.22 - (41.64 ± 2.31) kJ mol-1/2.303 RT and the disproportionation-combination rate constant ratio for isopropyl radicals has been found to fall from 0.52 at 518 K to 0.49 at 573 K.

AB - The gas phase pyrolyses of 2,2′-azoisobutane and azoisopropane have been investigated in the temperature range 471-573 K. The products of 2,2′-azoisobutane (AIB) decomposition result from the following elementary reactions. AIB k1→ 2t-C4H9 + N2 (1) 2t-C4H9 kd→ iC4H10 + iC4H8 (2) 2t-C4H4 kc→ 2,2,3,3-tetramethylbutane (3) The disproportionation-combination rate constant ratio, kd/kc, for t-butyl radicals has been determined as 2.60 ± 0.04 in the temperature range 483 to 515 K. In addition to the corresponding reactions (1) to (3) involving isopropyl radicals, azoisopropane (AIP) decomposition involves the abstraction reaction, iC3H7 + AIP ka→ C3H8 + AIP·. (4) In the temperature range, 518-573 K, ka is given by the expression, log10 ka/(kc)1/2/cm3/2 mol-1/2 s-1/2 = 5.26 ± 0.22 - (41.64 ± 2.31) kJ mol-1/2.303 RT and the disproportionation-combination rate constant ratio for isopropyl radicals has been found to fall from 0.52 at 518 K to 0.49 at 573 K.

UR - https://www.scopus.com/pages/publications/2242423817

U2 - 10.1039/F19777300803

DO - 10.1039/F19777300803

M3 - Article

AN - SCOPUS:2242423817

SN - 0300-9599

VL - 73

SP - 803

EP - 816

JO - Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases

JF - Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases

ER -

Comparison of the mechanisms of the thermal decompositions of 2,2′-azisobutane and azoisopropane

Abstract

Access to Document

Other files and links

Fingerprint

Cite this