Esters isocyanates

Synonyms AI3-015101 BRN 0744602 CCRIS 3742 Desmodur T80 2,4-Diisocyanato-l-methylbenzene Diisocyanatoluene 2,4-Diisocyanotoluene Hylene T Hylene TCPA Hylene TLC Hylene TM Hylene TM-65 Hylene TRF Isocyanic acid, methylphenylene ester Isocyanic acid, 4-methyl-/ 3-phenylene ester 4-Methylphenylene diisocyanate 4-Methylphenylene isocyanate Mondur TD Mondur TD-80 Mondur TDS Nacconate 100 NCI-C50533 Niax TDI Niax TDI-P NSC 4791 NSC 56759 RCRA waste number U223 Rubinate TDI 80/20 TDI 2,4-TDI TDI-80 Toluene 2,4-diisocyanate Tolyene-2,4-diisocyanate Tolylene-2,4-diisocyanate 2,4-Tolylene diiso-cyanate /n-Tolylene diisocyanate UN 2078. 

Synthesis of Amino Acid Ester Isocyanates Methyl (S)-2-lsocyanato-3-phenylpropanoate. 

Usually, the traditional routes to the synthesis of carbamic acid esters, isocyanates and ureas start from the toxic compound phosgene [10]. Consequently, the ability to synthesize these compounds from ubiquitous, cheap and safe C02, as an alternative starting material to phosgene, represents an appealing and highly eco-friendly variation to the conventional protocols which have in the past been based on phosgenation. Moreover, it also provides an attractive answer to the current widespread requests for environmental protection [11]. 

Durch Addition von Alkoholen oder Aminen an Phosphonsaure-ester-isocyanate in Di-ethylether oder Toluol erhalt man die entsprechenden Urethane oder Harnstoffe... 

Phosphorsaure-fluorid-ester-isocyanate werden mit Antimon(III)-fluorid aus Phos-phorsaure-chlorid-ester-isocyanatcn [20-50° (exotherm), danach 100°)351 352 bzw. mit schlechteren Ausbeuten aus Phosphorsaure-bis-[isocyanatJ-estern352 353 erhalten ... 

Cyclische Phosphorigsaure-amid-ester-isocyanate liefern mit Chlor in Tetrachlormethan z. B. Phosphorsaure-(2-chlor-ethylamid)-chlorid-isocyanate404 ... 

Thiophosphorsaure-amid-O-ester-isocyanate, bzw. -bis-[isocyanat]-O-ester sowie -amid-O-ester-isothiocyanate... 

In gleicher Weise wie Phosphorsaure-diestei-isocyanate (s.S. 616, 742) sind Thiophos-phorsaure-ainid-O-ester-isocyanate bzw. -bis-[isocyanat]-0-ester durch Einwirkung von Oxalylchlorid" 54 oder Phosgen553 auf prim. Amid-Gruppen von Thio-phosphorsaure-diamid-O-eslern zuganglich ... 

Zur Herstellung kann auch die Umsetzung entsprechender Phosphorigsaure-amid-ester-isocyanate bzw. -bis-[isocyanat]-ester mit Thiophosphorylchlorid herangezogen wer-... 

The product from Step 3 (179 mmol) was added to a solution of L-leucine t-butyl ester isocyanate (179 mmol) dissolved in 300 ml DMF, stirred 2 hours at ambient temperature, then stood overnight. The solvent was removed, the residue treated with heptane, and the mixture stirred at ambient temperature 2 hours. The precipitate was filtered and the product isolated in 69% yield. 

The preparation of L-leucine t-butyl ester isocyanate is described (1). 

SYNS 2,6-DiisocYANATO-i-METHYLBENZENE 2,6-DIISOCYANATOTOLUENE HYI.ENE TM 2-METHYI.-m-PHENYLENE ESTER, ISOCYANIC ACID 2-METHYL-m-PHENYLENE ISOCYANATE NUXTDI 2,6-TDI 2,6-TOLUENE DIISOCYANATE m-TOL- [ LENE DIISOCYANATE TOLYLENE-2,6-DI-ISOCYANATE... 

SYNTHESIS OF AMINO ACID ESTER ISOCYANATES METHYL [Pg.111]

Amino acid ester isocyanates are produced cleanly by this method and can often be used without purification. If desired, volatile amino acid ester isocyanates, such as the title compound, can be purified to analytical purity by Kugelrohr distillation. The amino acid ester isocyanates generated by this method are formed without detectable racemization (>99.5% ee) the er antiomeric purity of the isocyanates can be checked by trapping with (S)-l-phenylethylamine, followed by 1H NMR analysis of the resulting urea adducts.2 If this method is used to generate isocyanates of peptides, then efficient stirring is necessary to prevent epimerization of the peptide isocyanates.3 4... 

Amino acid ester isocyanates are useful synthetic building blocks, precursors to peptides and azapeptides, 7 8 chiral derivatizing agents,9 13 and reagents for the preparation of chiral chromatographic media.11 12 (S)-2-lsocyanato-3-phenylpropanoate (phenylalanine methyl ester isocyanate) has been used as a... 

SYNTHESIS OF AMINO ACID ESTER ISOCYANATES METHYL (S)-2-ISOCYANATO-3-PHENYLPROPANOATE. 

Isothiocyanates normally act as weaker electrophiles and need more drastic conditions to give the thioxo derivatives 76 also organic bases, such as pyridine, have been successfully employed76 for the cyclization step, so that this heterocyclization procedure may be carried out as a one-pot, three-component (enamino ester, isocyanate, organic base) reaction. Higher car-bamoylated products, such as 109, are smoothly hydrolyzed in aqueous 5% KOH to the pyrido[2,3-d]pyrimidines 11076 (Scheme 26). 

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