Heinrich Heydt

Phosphatriafulvenes - phosphaalkenes with inverse electron density

The phosphatriafulvenes 3a,b, accessible from the cyclopropenone 1 and the lithium phosphides 2, possess inverse electron density as indicated by structure B; this can also be deduced from ab initio calculations. In accord with the electronic structure, methyllithium attacks at a carbon atom of the three-membered ring (to 45), carboxylic acid chlorides effect P-acylation (to 6), and dimethyl acetylenedicarboxylate inserts into the P/Si bond (to 8).

New Phosphorus−Carbon Cage Compounds by Diels−Alder and Homo Diels−Alder Reactions of 1,3,5‐Triphosphabenzenes with Alkenes

Ethylene, various monosubstituted alkenes (acrylic acid derivatives, styrene), as well as some selected disubstituted alkenes (maleic acid derivatives, fumaric acid derivatives, norbornene, cyclopentadiene) undergo Diels−Alder reactions with the 1,3,5-triphosphabenzenes 1 under mild conditions to furnish the dihydrotriphosphabarrelenes 9, 11a−c, 13a−e, 15a−d, 17a,b, and 24. The monoadduct 26 as well as the diadducts 27 and 28 are isolated following the reaction with norbornadiene. Cyclopropene is the only alkene to undergo a Diels−Alder/homo Diels−Alder reaction sequence to afford the hexacyclic system 20.

PHOSPHORVERBINDUNGEN UNGEWOHNLICHER KOORDINATION, 6.1ABFANGVERSUCHE VON PHENYL-THIOXOUND PHENYL-SELENOXOPHOSPHAN MIT PROTISCHEN NUKLEOPHILEN

Abstract The thioxophosphole 6 undergoes Diels-Alder reaction with the triazolindiones 7a and b to the adducts 8a and b. Analogously 11a and b are formed from the selenoxophosphole 9 and the maleic acid derivatives 10a and b. The triazolindion reactions of 6, 9 and also of 12 suffer considerably under the presence of water. Apart from elemental sulfur and selenium on the one hand phosphole oxides (15) such as secundary products and triazolidindiones (19) on the other hand are formed. Thermolysis of the Diels-Alder adducts 8a and b in toluene proceeds unter [4 + 1] cycloreversion to 20 and phenyl thioxophosphan (21) which is trapped by alcohols (22,24) under production of phosphinothioates (23,25). Phenyl selenoxophosphane (27) is generated by photochemical decomposition of 11a and b. The trapping reaction with methanol leads to the phosphinoselenoate 29 which is transformed into the phosphonoselenoate 28 under the conditions of the photolysis.

Untersuchungen an diazoverbindungen und aziden—Li Thermolyse von 7-chlor-5-(diazomethyl)benzocyclo)-heptatrienen zu 8-chlor-benzocyclooctatetraenen

Zusammenfassung Die Reaktion von 7, 7-Dichlorbenzocycloheptatrien 3 mit den metallierten Diazomethylverbindungen 4a, b und 8a, b liefert unter Abspaltung entsprechender Metallhalogenide die 7-Chlor-5-diazomethylbenzocycloheptatriene 7a, b und 9a, b; Isomere des Typs 6 werden nicht gebildet. Kupfer(II)-acetylacetonat-katalysierte Thermolyse der Diazoverbindungen fuhrt unter Ringerweiterung zur Bildung von 8-Chlor-6-phosphoryl(bzw. carbonyl)-substituierten Benzocyclooctatetraenen 10a-d. Fur 10a wurde eine Rontgenstrukturanalyse durchgefuhrt.

Untersuchungen an Diazoverbindungen und Aziden. LVII: Tri- und Tetracyclen aus 5-(Diazomethyl)-5H-Benzocycloheptenen und 4-Phenyl-1,2,4-triazolin-3,5-dion

Zusammenfassung Die Phosphoryldiazomethane 10a und b gehen mit den 7-Alkylthiobenzocycloheptenylium-perchloraten 9a und b elektrophile Diazoalkansubstitution zu den 5-(Diazomethyl)-5 H -benzocycloheptenen 11a–11d ein. Selbst das nicht dissoziierte 7 kann grundsatzlich den gleichen Substitutionsprozess eingehen, wie die Reaktion mit 13 zu 14 zeigt. Mit 4-Phenyl-l,2,4-triazolin-3,5-dion (PTAD, 2 ) reagieren die Diazoverbindungen 11a–11d sowie 14 und 17 vermutlich uber die Betaine 18 zu den Cycloaddukten 19a–19f , in denen die Diazofunktion unverandert bleibt. Im Gegensatz dazu liefern die 5-(Diazomethyl)-5 H -benzocycloheptene 20a–20d mit 2 unter Stickstoff-Verlust die Tetracyclen 23a–23d ; fur 23c wurde eine Rontgenstrukturanalyse durchgefuhrt. Wir nehmen an, dass sich die Reaktion uber dipolartige Zwischenstufen ( 21,22,24 ) abspielt.

Organophosphorus compounds - 601. Reactions of phosphatriafulvenes with nucleophilic partners

Abstract The phosphatriafulvenes 1a,b - phosphaalkenes with inverse electron density - react primarily at the three-membered ring with nucleophilic reagents. From their reactions with organolithium compounds 2a-c and Grignard reagents 5a,b the cyclopropenylphosphines 4a-f are obtained after addition of chlorotrimethylsilane; of these products only 4a, d, and e were isolated and characterized. Methanolysis of products 4a-f yields the primary (7a-d) and secondary phosphines (9a,b) via cleavage of the PSi bond. Compound 1b reacts with the ynamines 10a,b through cleavage of the three-membered ring to yield the 1-phospha-1,3,5-hexadienynes 11a (X-ray structure) and 11b. The same phosphatriafulvene reacts with the cyclobutadienes 17a,b to furnish initially the 2-phosphabicyclohexenes 18a,b which, on stirring in chloroform at room temperature, undergo [2 + 2] cycloreversion to give the open-chain isomers 20a,b.

Diazoverbindungen, 65 Isomerisierungen im System 4-Diazo-1-buten/2.3-Diazabicyclo[3.1.0]hex-2-en/1.4-Dihydropyridazin/Diazo Compounds, 65 Isomerization Reactions in the System 4-Diazo-1-butene/2.3-Diazabicyclo[3.1.0]hex-2-ene/1.4-Dihydropyridazine

Abstract (Diazomethyl)diphenylphosphine oxide (2a) adds onto the 1-cyclopropene phosphonates 1a and c under formation of the 2.3-diazabicyclo[3.1.0]hex-2-enes 3a and c. 3a is easily converted into the 1.4-dihydropyridazine 5a. On the other hand the reaction of 1b with 2a directly affords the 1.4-dihydropyridazine 5b. The 2.3-diazabicyclo[3.1.0]hex-2-enes 3a and c isomerize to the allyl diazomethanes 4a and c on heating in benzene. In the case of the reactions 2b+1b as well as 6+1a the direct formation of allyl diazo compounds (4d and 8a respectively) is observed. In a novel reaction 9-diazofluorene (6) yields the 1.3-butadiene 9 when reacted with the cyclo-propene 1b.

Phosphorverbindungen ungewöhnlicher Koordination, 13. Abfangreaktionen von Phenyl-thioxophosphan durch [4+1]-CycIoaddition mit o-Chinonen/ Phosphorus Compounds with Unusual Coordination, 13 [1] Trapping Reactions of Phenyl Thioxophosphane by [4+1] Cycloaddition with o-Quinones

Abstract Phenyl thioxophosphane (1) - generated by thermal cycloreversion from 7 along with the dihydropyridazine 8 - is trapped by [4+1] cycloaddition with the o-quinones 9a-f by formation of the dioxaphospholsulfides 10a-f. Solvolysis of 10a-c, e and f with m ethanol yields the phenol derivatives 12a-e (in the case of 10b the isomer 12b′ is formed, too). This reaction is reversible (12a-c→10a-c) and accompanied by formation of the isomers 13a-c. The phenanthrene quinone methanide 14 is also suitable for the trapping reaction of 1 (→15→17).

Transformation of Phosphaalkynes into 1H- and 2H-Phosphirenes1

Abstract The 2H-phosphirene 4 is synthesized from the spirocyclic 3H-1,2,4-diazaphosphole 1 by low temperature photolysis. The isomeric 1H-phosphirenes 7 are formed by a [2+1]-cycloaddition process of chlorocarbenes, generated from diazirines. onto the triple bond of phosphaalkynes. When the 1-chlon-1H-phosphirenes 7 are allowed to react with a series of nucleophiles substitution occurs yielding the 1H-phosphirenes 9, 11 and 12. The existance of a phosphirenium cations, for instance 13 is discussed.

Organophosphorus Compounds, Part 168; 1,3-Dipolar Cycloaddition Reactions of 1,3,5-Triphosphinines with Nitrile Oxides

Phenylnitrile oxide as well as mesitylnitrile oxide underwent 1,3-dipolar cycloaddition reactions with the 1,3,5-triphosphinines 2 under mild conditions to furnish the condensed heterocyclic compounds 9 and 11, respectively. Oxadiphospholes 14 were accessible by fragmentation reactions of 11.