64833-96-1

Usage

Uses

Butyric-3,3-d2 Acid (CAS# 64833-96-1) is a useful isotopically labeled research compound.

Upstream product

• 25493-15-6 1-iodopropane-2,2-d₂ 
• 124-38-9 carbon dioxide 
• 64118-20-3 1-(3,3-2H₂)-butanol 
• 3652-84-4 1,1-dideuterio-1-bromoethane 
• 64-19-7 acetic acid 

Relevant academic research and scientific papers

Method of preparing beta-d2 alkyl acid compounds

The invention provides a method of preparing beta-d2 alkyl acid compounds. The method includes steps of: 1) performing a reduction reaction to a compound A with LiAlD4 to obtain a compound B; 2) performing -OD group protective reaction to the compound B to obtain an intermediate C; 3) performing a bromination reaction to the intermediate C to obtain a compound D; 4) under alkaline condition, performing a substitution reaction to the compound D and acetic acid to obtain the beta-d2 alkyl acid compounds. In the method, the alkyl acid, which is low in cost and is easy to obtain, is used as the initial raw material and is subjected to LiAlD4 reduction reaction, the -OD group protective reaction, the bromination reaction and the acetic acid substitution reaction to prepare the beta-d2 alkyl acid compounds. The method has simple process route and is free of expensive catalysts and the like during the reactions, is low in cost, and is high in total yield of the beta-d2 alkyl acid compounds. The method, when being amplified to gram-scale, has stable yield and good repeatability and is practicable and available.

Reactions of Ionized Dibutyl Ether

The reactions of ionized di-n-butyl ether are reported and compared with those of ionized n-butyl sec-butyl and di-sec-butyl ether.The main fragmentation of metastable (CH3CH2CH2CH2)O+. is C2H5. loss (ca. 85percent), but minor amounts (2-4percent of CH3., C4H7., C4H9., C4H10 and C4H10O are also eliminated.In contrast, C2H5. elimination is of much lower abundance (20 and 4percent, respectively) from metastable CH3CH2CH2CH2OCH(CH3)CH2CH3+. and 2O+., which expel mainly C2H6 and CH3. (35percent-55percent).Studies on collisional activation spectra of the C6H13O+ oxonium ions reveal that C2H5. loss from (CH3CH2CH2CH2)2O+. gives the same product, (CH3CH2CH2CH2+O=CHCH3) as that formed by direct cleavage of CH3CH2CH2CH2OCH(CH3)CH2CH3+..Elimination of C2H5. from (CH3CH2CH2CH2O+. is interpreted by means of a mechanism in which a 1,4-H shift to the oxygen atom initiates a unidirectional skeletal rearrangement to CH3CH2CH2CH2OCH(CH3)CH2CH3+., which than undergoes cleavage to CH3CH2CH2CH2+O=CHCH3 and C2H5..Further support for this mechanism is obtained from considering the collisional activation and neutralization-reionization mass spectra of the (C4H9)2O+. species and the behaviour of the labelled analogues of the (CH3CH2CH2CH2)2O+..The rate of ethyl radical loss is suppressed relative to those of alternative dissociations by deuteriation at the γ-position of either or both butyl substituents.Moreover, C2H5. loss via skeletal rearrangement and fragmentation of the unlabelled butyl group in CH3CH2CH2CH2OCH2CH2CD2CH3+. occurs approximately five times more rapidly than C2H4D. expulsion via isomerization and fission of the labelled butyl substituent.These findings indicate that the initial 1,4-hydrogen shift is influenced by a significant isotope effect, as would be expected if this step is rate limiting in ethyl radical loss.

Unimolecular Reactions of Isolated Organic Ions: the Chemistry of the Oxonium Ions CH3CH2CH2CH2(+)O=CH2 and CH3CH2CH2CH=O(+)CH3

The reactions of the metastable oxonium ions CH3CH2CH2CH2(+)O=CH2 and CH3CH2CH2CH=O(+)CH3 are reported and discussed.Both these isomers of C5H11O(+) expel predominantly CH2O (75 - 90percent of the metastable ion current), a moderate amount of C3H6 (5-15percent), a minor amount of CH3OH (2-8percent) and a very small proportion of H2O (0.5-3percent).All these processes give rise to Gaussian metastable peaks.The kinetic energy releases associated with fragmentation of these oxonium ions are similar, but slightly larger for dissociation of CH3CH2CH2CH=O(+)CH3.The behaviour of labelled analogues confirms that the reactions of CH3CH2CH2CH2(+)O=CH2 and CH3CH2CH2CH=O(+)CH3 are closely related, but subtly different.Elimination of CH2O and C3H6 is intelligible by means of mechanisms involving CH3CH(+)CH2CH2OCH3.This open-chain cation is accessible to CH3CH2CH2CH2(+)O=CH2 by a 1,5-H shift and to CH3CH2CH2CH=O(+)CH3 by two consecutive 1,2-H shifts (or, possibly, a direct 1,3-H shift).The rates of these 1,2-, 1,3- and 1,5-H shifts are compared with one another and also with the rates of CH2O and C3H6 loss from each of the two oxonium ions.The 1,5-H shift that converts CH3CH(+)CH2CH2OCH3 formed from CH3CH2CH2CH=O(+)CH3 into CH3CH2CH2CH2(+)O=CH2 prior to CH2O elimination is essentially unidirectional.In contrast, the corresponding step converting C5H11O(+) ions generated as CH3CH2CH2CH2(+)O=CH2 into CH3CH(+)CH2CH2OCH3 competes effectively with expulsion of CH2O and C3H6.The implications of the latter finding for the degree of concert in the hydrogen transfer and carbon-carbon bond fission steps in alkene losses from oxonium ions via routes that are formally isoelectronic with the retro 'ene' pericyclic process are emphasized.

Noncompeting Metastable Losses of Methyl and Ethylene from Gaseous Butanoic Acid Ions due to Isomerization Prior to Methyl Loss

Metastable C4H8O+. ions obtained from butanoic acid and ethyl butanoate undergo considerable γ-hydrogen exchange prior to losing ethylene, but little exchange prior to losing methyl.Therefore the two fragmentations are not directly competing, contrary to the general assumption that all reactions of an ion in the gas phase are competitive.It is concluded that metastable butanoic acid ions which lose methyl isomerize essentially irreversibly to CH3CH2C.HC(OH)2+ and/or CH3CH(C.H2)C(OH)2+ before the γ-methyl becomes exchanged.This accounts for the difference between γ-hydrogen exchange prior to the loss of methyl and ethylene without invoking isolated electronic states, as previously proposed.Butanoic acid ions generated by the McLafferty rearrangement of butanoate esters have a much weaker metastable loss of ethylene than directly ionized butanoic acid.Collisional activation experiments demonstrate that this results from more of the butanoic acid ions derived from ethyl butanoate than from butanoic acid isomerizing prior to collision.Variation in internal energy probably causes this difference in degree of isomerization with the source of the ion.