4744-08-5

Basic information

• Product Name: PROPIONALDEHYDE DIETHYL ACETAL
• Synonyms: PROPIONALDEHYDE DIETHYL ACETAL;PROPANAL DIETHYL ACETAL;1,1-DIETHOXYPROPANE;1,1-diethoxy-propan;4-Ethyl-3,5-dioxaheptane;Propane, 1,1-diethoxy-;propylene glycol diethyl ether;Propionaldehyde diethyl acetal,97%
• CAS NO: 4744-08-5
• Molecular Formula: C₇H₁₆O₂
• Molecular Weight: 132.2
• EINECS: 225-257-8
• Mol File: 4744-08-5.mol

Chemical Properties

• Boiling Point: 122.8 °C(lit.)
• Flash Point: 55 °F
• Appearance: /
• Density: 0.815 g/mL at 25 °C(lit.)
• Vapor Pressure: 16.5mmHg at 25°C
• Refractive Index: n20/D 1.389(lit.)
• Storage Temp.: Flammables area
• BRN: 1697731
• CAS DataBase Reference: PROPIONALDEHYDE DIETHYL ACETAL(CAS DataBase Reference)
• NIST Chemistry Reference: PROPIONALDEHYDE DIETHYL ACETAL(4744-08-5)
• EPA Substance Registry System: PROPIONALDEHYDE DIETHYL ACETAL(4744-08-5)

Safety Data

• Hazard Codes: F
• Statements: 11
• Safety Statements: 16-23
• RIDADR: UN 1989 3/PG 2
• WGK Germany: 3
• HazardClass: 3.1
• PackingGroup: II
• Hazardous Substances Data: 4744-08-5(Hazardous Substances Data)

Usage

Uses

Used in Chemical Industry:
Propionaldehyde diethyl acetal is used as a reducing agent for the aerobic epoxidation of alkenes, which is a crucial process in the synthesis of various chemicals and materials. Its reducing properties enable the conversion of alkenes to epoxides, which are valuable intermediates in the production of polymers, pharmaceuticals, and other specialty chemicals.
Used in Pharmaceutical Industry:
In the pharmaceutical industry, Propionaldehyde diethyl acetal may be utilized as an intermediate in the synthesis of various drugs and drug candidates. Its ability to act as a reducing agent can be harnessed to facilitate specific chemical transformations required for the production of targeted therapeutic compounds.
Used in Polymer Production:
Propionaldehyde diethyl acetal is also used in the production of polymers, where the epoxides derived from the aerobic epoxidation of alkenes can be further reacted to form polymers with specific properties. These polymers find applications in a wide range of industries, including automotive, construction, and consumer goods.

InChI:InChI=1/C7H16O2/c1-4-7(8-5-2)9-6-3/h7H,4-6H2,1-3H3

Synthetic route

Triethyl orthopropionate (115-80-0) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With palladium 10% on activated carbon; hydrogen In n-heptane at 100℃; under 67506.8 Torr; Temperature;	98.6%

triethylaluminum (97-93-8) + orthoformic acid triethyl ester (122-51-0) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
In dichloromethane at -20 - 20℃;	98%
In hexane at 35 - 40℃;	78%

ethanol (64-17-5) + 1-bromopropylamine → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With copper(l) chloride In cyclohexane at 45 - 65℃; for 12h; Temperature;	91%

propionaldehyde (123-38-6) + orthoformic acid triethyl ester (122-51-0) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With ammonium nitrate In ethanol at 20 - 36℃;	81.6%
Stage #1: propionaldehyde; orthoformic acid triethyl ester With ammonium nitrate; ethanol at 20 - 36℃; Stage #2: With sodium carbonate In water at 20℃; pH=7.5;	81.6%
With sulfuric acid

3,3-diethoxypropyl lithium → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With water In tetrahydrofuran at -78 - 20℃; for 2h;	80%
With water In tetrahydrofuran at -78 - 20℃; for 2h; Product distribution; also other electrophiles (D2O, (PhCH2)2S2, n-C3H7CHO, PhCHO, n-C7H15CHO, PhCH=NPh);	80%

ethanol (64-17-5) + propionaldehyde (123-38-6) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With calcium chloride at 25 - 35℃; for 10h; Temperature;	78.8%
With hydrogenchloride
With hydrogenchloride at 25℃; Gleichgewicht der Reaktion;

Triethyl orthopropionate (115-80-0) → 1,1-diethoxypropane (4744-08-5) + ethylpropylether (628-32-0)

Conditions	Yield
With palladium 10% on activated carbon; hydrogen In n-heptane at 150℃; under 67506.8 Torr; Temperature;	A 63% B 36.9%

diethoxymethyl acetate (14036-06-7) + diethylaluminium chloride (96-10-6) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
In diethyl ether at 20℃; for 4h;	53%

(E)-1-ethoxyprop-1-ene (4696-26-8) → (Z)-1-ethoxyprop-1-ene (4696-25-7) + 1,1-diethoxypropane (4744-08-5) + propionaldehyde (123-38-6)

Conditions	Yield
(sulphos)Rh(CO)2 In 1,2-dichloro-ethane at 100℃; for 1h;	A 22% B 31% C 14%

ethanol (64-17-5) + ethyl 1-propenyl ether (928-55-2) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With Fuller's Earth

tetraethoxy orthosilicate (78-10-4) + propionaldehyde (123-38-6) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With ethanol; phosphoric acid

ethylmagnesium bromide (925-90-6) + orthoformic acid triethyl ester (122-51-0) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With diethyl ether Hydrolyse mit verduennter Essigsaeure und sofortige Neutralisation;

(E)-3-Ureido-but-2-enoic acid ethyl ester (5435-44-9, 22243-66-9) + orthoformic acid triethyl ester (122-51-0) + acetylene (74-86-2) → malondialdehyde bis(diethyl acetal) (122-31-6) + 1,1-diethoxypropane (4744-08-5) + 1,1,4,4-tetraethoxy-2-butyne (3975-08-4)

Conditions	Yield
under 8826.09 - 12503.6 Torr;
at 170℃; under 8826.09 - 12503.6 Torr;

carbon monoxide (201230-82-2) + orthoformic acid triethyl ester (122-51-0) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With hydrogen; dicobalt octacarbonyl

n-propylmagnesium bromide (927-77-5) + orthoformic acid triethyl ester (122-51-0) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
In diethyl ether

3-chloro-1,1-diethoxy-propane (35573-93-4) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With water; naphthalen-1-yl-lithium 1.) THF, -78 deg C, 6 h, 2.) 20 deg C, 2 h; Yield given. Multistep reaction;
Multi-step reaction with 2 steps 1: lithium naphthalenide / tetrahydrofuran / 6 h / -78 °C 2: 80 percent / H2O / tetrahydrofuran / 2 h / -78 - 20 °C / also other electrophiles (D2O, (PhCH2)2S2, n-C3H7CHO, PhCHO, n-C7H15CHO, PhCH=NPh) View Scheme

sulfuric acid (7664-93-9) + propionaldehyde (123-38-6) + orthoformic acid triethyl ester (122-51-0) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
analoge Reaktion mit Orthoameisensaeure-tripropylester;

2-bromo-3,3-diethoxypropene (17592-40-4) + alcoholic KOH-solution → 1,1-diethoxypropane (4744-08-5)

orthoformic acid triethyl ester (122-51-0) + sunlight → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: 66 percent / formic acid / 24 h 2: 53 percent / diethyl ether / 4 h / 20 °C View Scheme

ethanol (64-17-5) + carbon monoxide (201230-82-2) + allyl alcohol (107-18-6) → 2-ethoxytetrahydrofuran (13436-46-9) + propan-1-ol (71-23-8) + Butane-1,4-diol (110-63-4) + 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With hydrogen; acetylacetonatodicarbonylrhodium(l) at 125℃; under 30003 Torr; for 2.5h; Product distribution; Further Variations:; reagent ratios;

acrylaldehyde diethyl acetal (3054-95-3) → 1,1-diethoxypropane (4744-08-5)

Conditions	Yield
With borane-ammonia complex; cobalt(II)(2,6-bis(morpholinomethyl)pyridine)bromide In methanol at 80℃; for 14h;	99 %Chromat.

ethanol (64-17-5) → diethyl ether (60-29-7) + 1,1-diethoxypropane (4744-08-5) + ethyl vinyl ether (109-92-2)

Conditions	Yield
at 280℃; for 4h; Reagent/catalyst; Autoclave; Inert atmosphere;

4-iodopyridine-2-carboxylic acid methyl ester (380381-28-2) + 1,1-diethoxypropane (4744-08-5) → 4-(3,3-Diethoxy-prop-1-ynyl)-pyridine-2-carboxylic acid methyl ester (663614-43-5)

Conditions	Yield
With triethylamine; palladium diacetate; copper(l) iodide; triphenylphosphine at 20℃; for 3h;	100%

1,1-diethoxypropane (4744-08-5) + 3-(dimethylphenylsilyl)-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-propene (251475-02-2) → 4-ethoxy-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-hexene

Conditions	Yield
With titanium tetrachloride In dichloromethane at -78℃; for 3h;	99%
With titanium tetrachloride In dichloromethane TiCl4, CH2Cl2, -78°C, 3 h;	99%

1,1-diethoxypropane (4744-08-5) + (4R)-4-ethyl-1,3-oxazolidin-2-one (98974-04-0) → (R)-3-(1-ethoxypropyl)-4-ethyl-1,3-oxazolidin-2-one (925427-50-5)

Conditions	Yield
With 10-camphorsufonic acid In dichloromethane at 55℃;	97%

5-iodo-1,2,3-trimethoxybenzene (25245-29-8) + 1,1-diethoxypropane (4744-08-5) → 1,1-diethoxy-3-(3,4,5-trimethoxyphenyl)-2-propyne

Conditions	Yield
With copper(l) iodide; bis-triphenylphosphine-palladium(II) chloride In triethylamine at 20℃; for 3h;	97%

1,1-diethoxypropane (4744-08-5) + 3-cyclohexyl-3-(dimethylphenylsilyl)-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-propene (252062-23-0) → (E)-1-cyclohexyl-4-ethoxy-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-hexene

Conditions	Yield
With titanium tetrachloride In dichloromethane at -78℃; for 3h;	95%
With titanium tetrachloride In dichloromethane TiCl4, CH2Cl2, -78°C, 3 h;	95%

1,1-diethoxypropane (4744-08-5) + 3-(dimethylphenylsilyl)-5-phenyl-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-pentene (252062-22-9) → (E)-6-ethoxy-1-phenyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxacarborolan-2-yl)-3-octene

Conditions	Yield
With titanium tetrachloride In dichloromethane at -78℃; for 3h;	94%
With titanium tetrachloride In dichloromethane TiCl4, -78°C, CH2Cl2, 3 h;	94%
With aluminium trichloride In dichloromethane AlCl3, CH2Cl2, -78°C, 0.5 h; -20°C for 2.5 h;	82%
With trimethylsilyl trifluoromethanesulfonate In dichloromethane TMSOTf, CH2Cl2, -78°C, 0.5 h; -20°C for 2.5 h;	30%

1,1-diethoxypropane (4744-08-5) + acetophenone (98-86-2) → 3-ethoxy-1-phenyl-pentan-1-one

Conditions	Yield
Stage #1: acetophenone With di-n-butylboryl trifluoromethanesulfonate; N-ethyl-N,N-diisopropylamine In dichloromethane at -78℃; for 0.5h; Stage #2: 1,1-diethoxypropane In dichloromethane at -78℃; for 0.5h;	90%

1,1-diethoxypropane (4744-08-5) + 7-chloro-4,6-dimethoxy-2,3-dihydrobenzofuran-3-one (3261-06-1) → (Z)-7-chloro-4,6-dimethoxy-2-(1-propylidene)-3(2H)-benzofuranone (129529-56-2)

Conditions	Yield
With titanium tetrachloride In dichloromethane for 24h; Ambient temperature;	89%

1,1-diethoxypropane (4744-08-5) + 1,3-diphenylpropanedione (120-46-7) → 2-(1-Ethoxy-propyl)-1,3-diphenyl-propane-1,3-dione (116863-89-9)

Conditions	Yield
With trimethylsilyl trifluoromethanesulfonate In dichloromethane at -78℃;	89%

1,1-diethoxypropane (4744-08-5) + (Z)-1-Phenyl-6-trimethylsilanyl-hex-4-en-1-ol (164076-17-9) → (2S,3S,6S)-2-Ethyl-6-phenyl-3-vinyl-tetrahydro-pyran

Conditions	Yield
With toluene-4-sulfonic acid for 24h; Product distribution; Ambient temperature; reactions of derivatives with var. acetals;	84%
With toluene-4-sulfonic acid for 24h; Ambient temperature;	84%

acetamide (60-35-5) + 1,1-diethoxypropane (4744-08-5) → N,N'-(propane-1,1-diyl)diacetamide (7073-48-5)

Conditions	Yield
With trifluorormethanesulfonic acid In dichloromethane for 0.25h; Heating;	83%
With sulfuric acid

1,1-diethoxypropane (4744-08-5) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → 3,3-diethoxy-2-methyl-propionaldehyde (22634-86-2)

Conditions	Yield
With trichlorophosphate at 70℃; for 2h; Vilsmeier reaction;	83%

1,1-diethoxypropane (4744-08-5) + ethyl vinyl ether (109-92-2) → 1,1,3-triethoxypentane (39595-61-4)

Conditions	Yield
Montmorillonite clay K-10 at 10 - 15℃;	80%
NdNaY at 0 - 25℃; for 0.5h;	61%
With iron(III) chloride
With iron(III) chloride
With boron trifluoride diethyl etherate at 65℃;

1,1-diethoxypropane (4744-08-5) → ethyl 1-propenyl ether (928-55-2)

Conditions	Yield
2-ethyl-N-(2-ethylhexyl)-1-hexanamine; toluene-4-sulfonic acid	77.5%
With quinoline; phosphorus pentoxide distillation at a bath temp. 150 deg C;	75%
With quinoline; phosphorus pentoxide vermutlich entsteht als Gemisch von cis- und trans-Form;
With sodium hydrogen sulfate vermutlich entsteht als Gemisch von cis- und trans-Form;
With silver-asbestos at 280℃; vermutlich entsteht als Gemisch von cis- und trans-Form;

1,1-diethoxypropane (4744-08-5) → (Z)-1-ethoxyprop-1-ene (4696-25-7)

Conditions	Yield
With 2-ethyl-N-(2-ethylhexyl)-1-hexanamine; toluene-4-sulfonic acid at 160℃; Distillation;	77.5%

1,1-diethoxypropane (4744-08-5) + propionaldehyde (123-38-6) + 3-(dimethylphenylsilyl)-5-phenyl-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-pentene (252062-22-9) → (2R*,4S*,4aR*,10bS*)-2,4-diethyl-1,4,4a,5,6,10b-hexahydro-10b-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2H-naphtho[2,1-c]pyran

Conditions	Yield
Stage #1: propionaldehyde; 3-(dimethylphenylsilyl)-5-phenyl-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-pentene With titanium tetrachloride In dichloromethane at -78℃; for 2h; Stage #2: 1,1-diethoxypropane In dichloromethane at 0℃; for 3h;	75%

1,1-diethoxypropane (4744-08-5) + propionaldehyde (123-38-6) + 3-(dimethylphenylsilyl)-5-phenyl-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-pentene (252062-22-9) → C6H4(CH2)2CHCH(C2H5)OCH(C2H5)CH2CBO2C2(CH3)4 (347868-66-0)

Conditions	Yield
With titanium tetrachloride; sodium hydrogencarbonate In dichloromethane B salt mixed with TiCl4 at -78°C, stirred at -78°C for 2 h, treated with aldehydes at -78°C, stirred at 0°C for 3 h,treated with aq.NaHCO3; extd.(AcOC2H5), chromy.(silica gel);	75%

1,1-diethoxypropane (4744-08-5) + 1,1'-oxybisethene (109-93-3) → 1,1,3,5-tetraethoxyheptane

Conditions	Yield
at 0 - 50℃; for 2.5h; Time;	75%

1,1-diethoxypropane (4744-08-5) + P,P-diphenylphosphinothioic amide (17366-80-2) → C18H20NPS (1138700-42-1)

Conditions	Yield
at 120 - 160℃;	73%

1,1-diethoxypropane (4744-08-5) + di-tert-butyl 1-(6-methoxypyridin-3-yl)hydrazine-1,2-dicarboxylate (1338466-39-9) → 3-methylpyrrolo<3,2-b>pyridinee (138469-76-8)

Conditions	Yield
Stage #1: 1,1-diethoxypropane; di-tert-butyl 1-(6-methoxypyridin-3-yl)hydrazine-1,2-dicarboxylate With sulfuric acid In water for 1h; Reflux; Inert atmosphere; Stage #2: With sodium carbonate In water Saturated solution; Inert atmosphere;	72%

1,1-diethoxypropane (4744-08-5) + trimethylsilyl cyanide (7677-24-9) → diethyl ether-acetonitrile (87271-68-9)

Conditions	Yield
zinc(II) iodide at 25℃; for 3h;	71%

1,1-diethoxypropane (4744-08-5) + Phenoxymagnesium bromide (35770-74-2) → 1,1-bis(2-hydroxyphenyl)propane (34240-91-0)

Conditions	Yield
In benzene for 24h; Heating;	70%

1,1-diethoxypropane (4744-08-5) + benzamide (55-21-0) → N-(n-propyl)benzamide (10546-70-0)

Conditions	Yield
With triethylsilane; trifluoroacetic acid In acetonitrile at 22℃; for 18h;	65%

Upstream product

• 78-10-4 tetraethoxy orthosilicate 
• 123-38-6 propionaldehyde 
• 64-17-5 ethanol 
• 122-51-0 orthoformic acid triethyl ester 
• 5435-44-9 (E)-3-Ureido-but-2-enoic acid ethyl ester 
• 74-86-2 acetylene 
• 3054-95-3 acrylaldehyde diethyl acetal 
• 115-80-0 Triethyl orthopropionate 
• 201230-82-2 carbon monoxide 
• 107-18-6 allyl alcohol 
• 4696-26-8 (E)-1-ethoxyprop-1-ene 
• 17592-40-4 2-bromo-3,3-diethoxypropene 
• 7664-93-9 sulfuric acid 
• 97-93-8 triethylaluminum 

Downstream Products

• 116863-89-9 2-(1-Ethoxy-propyl)-1,3-diphenyl-propane-1,3-dione 
• 123-38-6 propionaldehyde 
• 591-22-0 3,5-Lutidine 
• 160590-01-2 7-methoxy-3-phenyl-1H-pyrrolo[2,3-c]pyridine 
• 138469-76-8 3-methylpyrrolo<3,2-b>pyridinee 
• 141287-63-0 3-methyl-5-(phenylmethoxy)-1H-indol-1-amine 
• 3054-95-3 acrylaldehyde diethyl acetal 
• 55064-41-0 2-aminopropionaldehyde diethyl acetal 
• 106094-89-7 α-chloroβ-(phenylseleno)propyl ethyl ether 

Relevant articles and documents

Preparation method 1 and 1 - diethoxypropane

The invention discloses a preparation method of 1-1 - diethoxypropane. Ethanol and propionaldehyde are used for contacting with a solid acid catalyst under the condition of vaporization, and water is taken out. 1,1 - Diethoxypropane crude product is discharged from the bottom side of the rectification tower, and the rectification obtains 98%, 1 diethoxypropane with a purity greater than 1 . To the method, the problem of long reaction time at low temperature is solved, the single conversion rate is relatively high, 1 and 1 - diethoxy propane in the obtained crude product is 50 - 80%, 99% diethoxypropane can be obtained through rectification, the highest yield can reach 1 97% 1 - continuous feeding is facilitated, and pipeline continuous reaction is carried out.

SELECTIVE ACETALIZATION / ETHERIFICATION PROCESS

The present invention relates to a selective process for preparing acetals or ethers. In particular, the process involves a selective catalytic hydrogenolysis of a trihydrocarbyl orthoesterso as to control the extent of dealcoholation to afford either the corresponding acetal or ether product. Ether products preparable by means of the present invention include ethers which are suitable for use as base stocks in lubricating compositions.

Phosphine-free cobalt pincer complex catalyzed: Z -selective semi-hydrogenation of unbiased alkynes

Herein, we report a novel, molecularly defined NNN-type cobalt pincer complex catalyzed transfer semi-hydrogenation of unbiased alkynes to Z-selective alkenes. This unified process is highly stereo- and chemo-selective and exhibits a broad scope as well as wide functional group tolerance. Ammonia-borane (AB), a bench-stable substrate with high gravimetric hydrogen capacity, was used as a safe and practical transfer hydrogenating source.

COBALT COMPLEXES, PROCESS FOR PREPARATION AND USE THEREOF

The present invention discloses a cobalt compound of formula (I), a process for the preparation and use thereof. The present invention further relates to a pharmaceutical composition and a method inhibition of Tau Aggregation in a subject in need thereof using compound of formula (I).

Method for preparing 2,4-heptadienal

The invention discloses a method for preparing 2,4-heptadienal. Heptadienal is prepared by taking propyl aldehyde as a starting material through the following three reaction steps: (1), synthesizing acrolein diethyl acetal through absolute ethyl alcohol and anhydrous calcium chloride; (2), synthesizing 1,1,3,5-tetraethoxyheptane through acrolein diethyl acetal, BF3 diethyl ether and vinyl ether; and (3), synthesizing trans-2-trans-4-heptadienal through 1,1,3,5-tetraethoxyheptane and hydrochloric acid. The method disclosed by the invention has the beneficial effects that raw materials are easily obtained, and cheap; a condition is easily controlled and operated; and, the product is relatively low in cost and better in quality, and is suitable for large-scale production.

Decomposition of a Β-O-4 lignin model compound over solid Cs-substituted polyoxometalates in anhydrous ethanol: acidity or redox property dependence?

Production of aromatics from lignin has attracted much attention. Because of the coexistence of C–O and C–C bonds and their complex combinations in the lignin macromolecular network, a plausible roadmap for developing a lignin catalytic decomposition process could be developed by exploring the transformation mechanisms of various model compounds. Herein, decomposition of a lignin model compound, 2-phenoxyacetophenone (2-PAP), was investigated over several cesium-exchanged polyoxometalate (Cs-POM) catalysts. Decomposition of 2-PAP can follow two different mechanisms: an active hydrogen transfer mechanism or an oxonium cation mechanism. The mechanism for most reactions depends on the competition between the acidity and redox properties of the catalysts. The catalysts of POMs perform the following functions: promoting active hydrogen liberated from ethanol and causing formation of and then temporarily stabilizing oxonium cations from 2-PAP. The use of Cs-PMo, which with strong redox ability, enhances hydrogen liberation and promotes liberated hydrogen transfer to the reaction intermediates. As a consequence, complete conversion of 2-PAP (>99%) with excellent selectivities to the desired products (98.6% for phenol and 91.1% for acetophenone) can be achieved.

Method for synthesizing thiacloprid drug intermediate 1,1-diethoxypropane

The invention provides a method for synthesizing a thiacloprid drug intermediate 1,1-diethoxypropane. The method comprises the following steps: adding 1.5mol of ethanol, 0.62mol of cuprous chloride, 500ml of cyclohexane and 2.1-2.6mol of 1-bromopropionamide solution into a reactor; controlling the stirring speed to be 110-140rpm; raising the solution temperature to 60-65 DEG C, and refluxing for 2-5 hours; reducing the solution temperature to be 40-45 DEG C; keeping on reacting for 5-7 hours; reducing the solution temperature to be 3-8 DEG C; standing for 10-15 hours, layering the solution to separate an oil layer, washing with acetamide, mixing water layers, washing with succinonitrile and triethylene glycol, dehydrating with a dehydrating agent, distilling at reduced pressure, and collecting distillate at 100-108 DEG C; and recrystallizing in N-methylformamide to obtain 1,1-diethoxypropane.

Modelling proposed intermediates in the hydrocarbonylation of alkenes catalysed by rhodium complexes of PBui3 and PPr i3

In ethanol, hydrocarbonylation reactions of alkenes catalysed by triethylphosphine complexes of rhodium give alcohols as the products with low linear selectivity, whilst rhodium complexes of PPri3 or PBui3 give mainly aldehydes, again with low linear selectivity. Modelling the proposed acyl intermediates by studying [Rh(C(O)Me)(CO)m(L)4-m] (L = PPri3 or PBui3) shows that they exist as monophosphine species under the normal reaction conditions. In the absence of CO, [Rh(=C(OH)Me)(CO) L2]+ can also be formed. The implications of these NMR studies for the chemo- and regio-selectivity of the hydrocarbonylation reactions are discussed. The Royal Society of Chemistry.

ULTRAPURE 4-METHYLPYRAZOLE

Disclosed is an ultrapure 4-methylpyrazole containing less than 0.1% pyrazole and containing less than 10 ppm each of hydrazine and nitrobenzaldehyde. The ultrapure 4-methylpyrazole is prepared by a novel process so that less than 0.01% of ethylvinyl ether is present.

ULTRAPURE 4-METHYLPYRAZOLE

Disclosed is an ultrapure 4-methylpyrazole containing less than 0.1% pyrazole and containing less than 10 ppm each of hydrazine and nitrobenzaldehyde. The ultrapure 4-methylpyrazole is prepared by a novel process so that less than 0.01% of ethylvinyl ether is present.