Pomeranz

Zeiscl, [hid 7 4 I ncdikt and BaiulxTgcr, Ibid. Herzig, Ibid, g, 544. Cf. Pomeranz, Ibid. 12, 383. J. Herzig and H. Meyer, Ibid. 7. 437- 

Instead of red phosphorus and water the potash bulbs contain a solution consisting of arsenious anhydride 

It has been stated that this method is unreliable on account of the action of mcthylic iodide on the arsenical liquid but further investigation shows that accurate re suits are obtained if the arsenious solution is less con 

Zeisel s method does not distinguish between me-thoxyl and ethoxyl should this be necessary, the alkyl iodide must be prepared in quantity sufficient for its 

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Pomeranz-Fntsch Synthesis, Isoquinolines aie available fiom the cycUzation of benzalamiaoacetals undei acidic conditions (165). The cyclization is preceded by the formation of the Schiff base (33). Although the yields ate modest, polyphosphoric acid produces product in all cases, and is especially useful for 8-substituted isoquinolines (166). 

Y. Pomeranz, Wheat Chemisty and Technology, 3rd ed., American Association of Cereal Chemists, St. Paul, Minn., 1988. 

Poly (vinyl pyrrol idones) polymerization, 1, 271 Polyviologens synthesis, 1, 286 Pomeranz-Fritsch synthesis isoqutnolines, 2, 428 6, 218 Pongapin synthesis, 4, 710 Poranthericine, 4, 494 ( )-Porantherine synthesis, 2, 377 Porphin, 4, 386 structure, 4, 378 Porphin, mcso-aryltri-p-tolyl-synthesis, 4, 230 Porphin, mcso-tetraalkyl-synthesis, 4, 230 Porphin, mcso-tetraaryl-synthesis, 4, 230 Porphin, mcso-tetraferrocenyl-synthesis, 4, 230 Porphin, meso-tetraphenyl-synthesis, 7, 767 Porphobilinogen biosynthesis, 1, 100... 

POMERANZ - FRITSCH SCHLITTER MULLER I soquinoDna Synthesis... 

Isequinoline synthesis Irom aromatic aldehydes and an aminoacetal (Pomeranz-Frttsch) or from phenethylamines and glyonal acetal (Schlitter-Muller). 

The Pomeranz-Fritsch reaction involves the preparation of isoquinolines 4 via the acid-mediated cyclisation of the appropriate aminoacetal intermediate 3. The best yields are usually obtained when the benzaldehyde portion 1 has electron-donating substituents in the 3- or 3,4- positions relative to the aldehyde. 

Of the well-known methods to prepare isoquinolines, including the Pictet-Spengler and Bischler-Napieralski cyclisation, the Pomeranz-Fritsch reaction is the only direct generally accepted method for the construction of the fully unsaturated isoquinoline ring system. 

Toward the end of the 19 century both Pomeranz and Fritsch independently reported the preparation of isoquinolines by the reaction of aminoacetaldehyde dimethyl acetal 2 (R = Me) with aromatic aldehydes 1 followed by cyclisation in acidic media. " Unfortunately yields were often poor and not always reproducible. This has prompted the search for various improvements and modifications on the original theme, including the use of reagents other than strong mineral acid which tends to destroy the intermediate imine. ... 

The Bobbitt modification is the most widely used variation of the Pomeranz-Fritsch reaction. This modification involves cyclisation of benzylaminoacetal 10, usually prepared from the classical Pomeranz-Fritsch imine 9, to yield 4-hydroxy derivatives 11. The success of this method can be attributed to avoiding treatment and thus (partial) destruction of imine 10 under strongly acidic conditions. 

The Jackson modification involves cyclisation of iV-tosylated amine 12 and provides a complementary method to the classical Pomeranz-Fritsch reaction for entry into the fully unsaturated ring system 13. Amine 12 can be prepared from either the Pomeranz-Fritsch-Bobbitt imine 10 or reaction of benzylhalide 14 and the corresponding sodium anion 15. ... 

The Schlittler-Muller variation of the Pomeranz-Fritsch reaction involves reaction of diethoxyethanal 17 with benzylamine 16 to prepare the desired imine 18. Intermediate 18 is subsequently cyclised to substituted isoquinoline 19. The advantage here lies in the fact that the initial condensation can still take place between an aldehyde and an amine. 

A number of Lewis acids have been utilized in the Pomeranz-Fritsch reaction, including polyphosphoric acid and boron trifluoride-trifluoroacetic anhydride. Under the latter conditions yields were best when electron-donating groups were present in the 3- or 3, 4- position of imine 20, whereas unactivated aldehydes failed to cyclise at all. ... 

Hydroxyquinoline 28 was synthesized in excellent yield via cyclisation of the appropriate Pomeranz-Fritsch-Bobbitt imine 27. The desired amine 27 was prepared via hydride reduction of the classical Pomeranz-Fritsch imine. 

The Pomeranz-Fritsch-Bobbitt reaction has been utilized for the preparation of 4-hydroxy tetrahydroisoquinoline 31 in excellent yield. In this example 2,5-disubstituted benzaldehyde 29 has been successfully used as the reacting partner. 

A concise total synthesis of (7 )-Reticuline has been reported using the Pomeranz-... 

The Pomeranz-Fritsch-Bobbitt cyclisation of activated amino-acetal 38 yielded the desired 4-hydroxyquinoline 39 in acceptable yield. The non-obvious regioselectivity of the cyclisation can be attributed to the overriding para-directing effect of alkoxy groups. ... 

Treatment of substituted pyrollidinone 42 with a Lewis acid, rather than simple protic acid, lead to a Pomeranz-Fritsch-Bobbitt type condensation to yield indolizinone 43 as a single diastereomer. ... 

Diazaphenanthrene 53 has been prepared via the Schlittler-Muller variation of the Pomeranz-Fritsch reaction in moderate yield. ... 

While examining possible approaches to the sempervirine ring system Stevens found that when the pyridinium salt 238 was treated with acid a Pomeranz-Fritzch type eychzation occurred leading to 239. Without the protective influence of the benzyl group, attack at the indole nitrogen atom took place yielding 240. 

Lazarou J, Pomeranz BH, Corey PN. Incidence of adverse drug reactions in hospitalized patients a meta-analysis of prospective studies. JAMA. 1998 Apr 15 279(15) 1200-5. 

Mahon, T.J., Color measnrement of food. Cereal Foods World, 38, 21, 1993. Pomeranz, Y. and Meloan, C.E., Food Analysis Theory and Practice, 3rd ed., Chapman Hall, New York, 1994. 

U. Koch-Pomeranz, H.-J. Hansen, and H. Schmid, Helv. Chim. Acta 58, 178 (1975). 

Horne R and Weinman J (1999) Patients beliefs about prescribed medicines and their role in adherence to treatment in chronic physical illness. J Psychosom Res 47(6) 555-567 Kannisto V, Lauritsen J, Thatcher AR et al. (1994) Reductions in mortality at advanced age several decades of evidence from 27 countries. Population and development review 20(4) 793-810 Lazarou J, Pomeranz BH, Corey PN (1998) Incidence of adverse drug reactions in hospitalized patients a meta- analysis of prospective studies. JAMA 279(15) 1200-1205 LeSage J (1991) Polypharmacy in geriatric patients. Nurs Clin North Am 26(2) 273-290 Pitkala KH, Strandberg TE, Tilvis RS (2001) Is it possible to reduce polypharmacy in the elderly ... 

This non-destructive technique is a very suitable tool for rapid in-line analysis of inorganic additives in food products (Price and Major, 1990 Anon, 1995). It can be readily used by non-skilled operators, and dry materials can be pressed into a pellet or simply poured into a sample cup. The principles of this technique related to food analysis are described by Pomeranz and Meloan (1994). A useful Internet site is http //www.xraysite.com, which includes information about different XRF instruments from various companies. Wavelength dispersive X-ray fluorescence (WD-XRF) or bench-top energy dispersive (ED-XRF) instruments are available. XRF is a comparative technique, thus a calibration curve needs to be established using food products of the same type as those to be... 

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