3,9-divinyl-2,4,8,10-tetraoxaspiro (5.5) undecane

The correct title of this article is " 3,9-divinyl-2,4,8,10-tetraoxaspiro [5.5] undecane ". This notation is not possible in Wikipedia due to technical restrictions .

Structural formula
General
Surname	3,9-divinyl-2,4,8,10-tetraoxaspiro [5.5] undecane
other names	3,9-divinylspirobi ( m -dioxane) Diallylidene pentaerythritol Pentaerythritol diacrolein acetal DVTOSU
Molecular formula	C 11 H 16 O 4
Brief description	white crystalline solid
External identifiers / databases
CAS number 78-19-3 EC number 201-092-7 ECHA InfoCard 100,000,994 PubChem 66218 Wikidata Q17521015
properties
Molar mass	212.24 g mol −1
Physical state	firmly
Melting point	43-46 ° C 42-43 ° C
boiling point	108-110 ° C at 1 mm Hg 108-110 ° C at 2 mm Hg 93-94 ° C at 1 mm Hg 138-141 ° C at 12 mm Hg
safety instructions
GHS labeling of hazardous substances no GHS pictograms Caution H and P phrases H: 302 P: 312
Toxicological data	3250 mg kg −1 ( LD 50 ,  rat ,  oral ) 7920 mg kg −1 ( LD 50 ,  rabbit ,  transdermal ) 320 mg kg −1 ( LD 50 ,  mouse ,  iv )
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

3,9-divinyl-2,4,8,10-tetraoxaspiro [5.5] undecane , DVTOSU for short , is a bicyclic organic molecule with a central quaternary carbon atom , the spiro atom , to which two alicyclic rings are linked, each containing five atoms. According to the nomenclature proposed by Adolf von Baeyer , the resulting spiro compound is a spiro [5.5] undecane, or because of the four oxygen atoms it contains, a 2,4,8,10-tetraoxaspiro [5.5] undecane, which is in the 3- and 9-position each carries an allyl group . DVTOSU is a diallylacetal and the precursor for the isomeric ketene acetal monomer 3,9-diethylidene-2,4,8,10-tetraoxaspiro [5.5] undecane , or DETOSU for short, which is a building block for polyorthoesters .

presentation

Condensation products of acrolein and pentaerythritol were first described in 1950. The synthesis proceeds according to the general manufacturing instructions for acetals at acidic pH (pH 3-5) by reacting an alcohol with an excess of aldehyde, which is stabilized with hydroquinone in the case of acrolein, which tends to polymerize at elevated temperatures .

After 19 hours of refluxing, neutralization of the oxalic acid , removal of the excess aldehyde and the water of reaction, the residue is fractionated under vacuum and 87% of theory Obtained diallylidene pentaerythritol. After recrystallization from 60% methanol, pure DVTOSU is obtained in 79% yield with a boiling point of 108-110 ° C. at 2 torr and a melting point of 42-42 ° C. The degree of conversion to acetal is determined by the equilibrium constant of the reaction:

The most common technique to complete the acetal formation reaction is to remove the water of reaction by azeotropic distillation with organic solvents that are not miscible with water, such as. B. benzene or toluene . In addition to the tendency of acrolein to polymerize at elevated temperatures, its high volatility at elevated temperatures causes problems such as those required for the removal of water. The low space-time yields of the acetal formation reaction require long reaction times at elevated temperatures, at which the nucleophilic addition of water and alcohol to the double bond of the unsaturated aldehyde also leads to undesired by-products. Adapting the reaction conditions to these requirements enables DVTOSU to be produced in 80% yield after a reaction time of 50 minutes at a reaction temperature of 80 ° C. and a 20% excess of aldehyde. The removal of the water of reaction by azeotropic distillation with benzene as ( entrainer ) shortens the reaction time to 10 hours, with DVTOSU in a yield of 75% of theory after fractional distillation. with a boiling point of 138-141 ° C at 12 mm HG. Even under very gentle (room temperature) and continuous process conditions, 1,3-diols can be converted into cyclic acetals with acrolein by continuous extraction with z. B. n -hexane can be produced in yields of up to 90%.

properties

3,9-divinyl-2,4,8,10-tetraoxaspiro [5.5] undecane is a white, crystalline powder in its pure state. Because of its low tendency to crystallize, DVTOSU is often sold as a liquid. The strongly fluctuating information on the yields and boiling points in the first fractional distillation indicate side reactions or by-products, e.g. B. by rearrangement of the double bonds or nucleophilic addition. The representation of the pure DVTOSU as a solid requires repeated recrystallization from hydrocarbons, e.g. B. pentane or n- hexane or aqueous methanol.

use

Alcohols such as B. methanol, and acids, such as. B. acetic acid can be added in a nucleophilic addition reaction to the allylic double bonds of diallylidenepentaerythritol to give the corresponding 3,9-dimethoxyethyl or 3,9-diacetoxyethyl-2,4,8,10-tetraoxaspiro [5.5] undecane. Likewise, hydrogen chloride add up in 80% yield or hydrogen cyanide in 50% yield to give the corresponding 3,9-bis (2-chloroethyl) - or 3,9-bis (2-cyanoethyl) -2,4,8,10- tetraoxaspiro [5.5] undecane. Diallylidenepentaerythritol reacts in the presence of strong acids, such as. B. boron trifluoride diethyl etherate , with diols or diacids to form rubbery polymers, which can be crosslinked to hard resins with further addition of acid and elevated temperatures. According to the authors, the terminal carbon atoms of the allyl groups of the DVTOSU are linked to the di- or polyol via ether bonds. The diallylacetal 3,9-divinyl-2,4,8,10-tetraoxaspiro [5.5] undecane, DVTOSU, is the starting compound for the ketene diacetal 3,9-diethylidene-2,4,8,10-tetraoxaspiro [5.5] undecane , DETOSU which is created by shifting the double bonds from the allyl to the vinyl position.

DETOSU is important as a reactive monomer for the formation of polyorthoesters.

Individual evidence

1. ↑ ^{a b c d e f g h i} Entry on 3,9-divinyl-2,4,8,10-tetraoxaspiro [5.5] undecane at TCI Europe, accessed on July 28, 2014.
2. ↑ ^{a b c d} H. Schulz, H. Wagner: Synthesis and conversion products of acrolein . In: Angewandte Chemie . tape 62 , no. 5 , 1950, pp. 105-118 , doi : 10.1002 / anie.19500620502 .
3. ^ ^{A b} Frank Brown, DE Hudgin, RJ Kray: Polymers from the Unsaturated Bisacetals of Pentaerythritol . In: Journal of Chemical & Engineering Data . tape 4 , no. 2 , 1959, p. 182–187 , doi : 10.1021 / je60002a020 ( PDF ( Memento from September 24, 2015 in the Internet Archive )).
4. ↑ ^{a b c} R. F. Fischer, CW Smith: Cyclic Acrolein Acetals . In: The Journal of Organic Chemistry . tape 25 , no. 3 , 1960, p. 319-324 , doi : 10.1021 / jo01073a002 .
5. ↑ ^{a b c} J. V. Crivello, R. Malik, Y.-L. Lai: Ketene acetal monomers: Synthesis and characterization . In: Journal of Polymer Science Part A: Polymer Chemistry . tape 34 , no. 15 , 1996, pp. 3091-3102 , doi : 10.1002 / (SICI) 1099-0518 (19961115) 34:15 <3091 :: AID-POLA1> 3.0.CO; 2-0 .
6. ↑ Wolfgang Holland: The nomenclature in organic chemistry . VEB German publishing house for basic industry, Leipzig 1969, p. 81.
7. ↑ J. Heller, KJ Himmelstein: Poly (ortho ester) biodegradable polymer systems . In: Methods in enzymology . tape 112 , 1985, pp. 422-436 .
8. ↑ Patent DE858406 : Process for the production of unsaturated cyclic acetals. Published on December 8, 1952 , applicant: Deutsche Gold- und Silber-Scheideanstalt formerly Roessler, inventor: H. Wagner. ‌
9. ↑ Patent US4108869 : Preparation of an acetal from a diol and acrolein. Published on August 22, 1978 , Applicant: EI Du Pont de Nemours and Co., Inventor: HB Copelin. ‌
10. ↑ Data sheet 3,9-Divinyl-2,4,8,10-tetraoxaspiro [5.5] undecane from Sigma-Aldrich , accessed on July 20, 2014 ( PDF ).