Tartaric acid derivatives formation with

A patent procedure for formation of compounds 19 from simple tartaric acid derivatives has appeared <06USP047129> and various new routes to chiral dioxolanones include synthesis of dioxolan-2-ones either by transition metal-mediated asymmetric synthesis <06T1864> or enzyme-mediated kinetic resolution <06H(68)1329> and a new synthesis of the chiral dioxolan-4-ones 21 from lactic or mandelic acid involving initial formation of intermediates 20 with trimethyl orthoformate in cyclohexane followed by reaction with pivalaldehyde <06S3915>. 

Photocyclization of A -alkylfuran-2-carboxyanilides conducted in inclusion crystals with optically active tartaric acid-derived hosts led to the formation of tricyclic /ra r-dihydrofuran compounds with up to 99% ee <1996JOC6490, 1999JOC2096>. 2-(/>-Alkoxystyryl)furans underwent photocyclization to give 5-(3-oxo-(/ )-butenyl)benzo[ ]furans as the predominant isomers in undehydrated dichloromethane as shown in Equation (59). The intermediate alkyl enol ether could be obtained by performing the reaction in anhydrous benzene <1999OL1039>. 

Shiga, T., Ohba, M., and Okawa, H. (2004) A series of trinuclear Cu Ln Cu complexes derived from 2,6-di(acetoacetyl)pyridine synthesis, structure, and magnetism. Inorganic Chemistry, 43, 4435 446. Albrecht, M., Schmid, S., Dehn, S., et al. (2007) Diastereoselective formation of luminescent dinuclear lan-thanide(III) helicates with enantiomerically pure tartaric acid derived bis(P-diketonate) ligands. New Journal of Chemistry, 31, 1755-1762. 

CAB 2, R = H, derived from monoacyloxytartaric acid and diborane is also an excellent catalyst (20 mol %) for the Mukaiyama condensation of simple enol silyl ethers of achiral ketones with various aldehydes. The reactivity of aldol-type reactions can, furthermore, be improved, without reducing the enantioselectivity, by use of 10-20 mol % of 2, R = 3,5-(CF3)2C6H3, prepared from 3,5-bis(trifluoromethyl)phenyl-boronic acid and a chiral tartaric acid derivative. The enantioselectivity could also be improved, without reducing the chemical yield, by using 20 mol % 2, R = o-PhOCgH4, prepared from o-phenoxyphenylboronic acid and chiral tartaric acid derivative. The CAB 2-catalyzed aldol process enables the formation of adducts in a highly diastereo- and enantioselective manner (up to 99 % ee) under mild reaction conditions [47a,c]. These reactions are catalytic, and the chiral source is recoverable and re-usable (Eq. 62). 

Utilization of the single hydrogen bond between pyridine and benzoic acids in SLCP s has been a source of inspiration for other groups in the development of main-chain supramolecular polymers based on diacids and dipyridines.53-56 Supramolecular rod-coil polymers have been developed by assembly of 4,4 -bipyridines and telechelic polypropylene oxide with benzoic acid end-groups, which show highly ordered liquid crystalline phases.57 The use of tartaric acid derivatives in combination with bipyridine units resulted in the formation of hydrogen-bonded, chiral main-chain LCP s, as has been shown by circular dichroism measurements, optical microscopy, and X-ray data.58,59... 

The components effectively incorporated into the polyassociation depend in particular on the nature of the core groups and on the interactions with the environment, so that supramolecular polymers possess the possibility of adaptation by association/growth/dissociation sequences. The selection of components may occur on the basis of size commensurability [18], of compatibility in chemical properties, in charge, in rigidity/flexibility, etc. An example is given by the formation of homochiral helical fibers with chiral selection from a racemic mixture of monomeric tartaric acid derivatives LU2 = LP2 -I- DU2 -I- DP2(LU2LP2)n + (DU2DP2)n (see Section II.C) [16],... 

Optically active (2R,3R)-dimethoxysuccinimide derivatives 4, prepared from (.R,./ -tartaric acid, arc reduced in excellent yield with high stereoselectivity by sodium borohydride in ethanol at 0- 5 °C to furnish a 20 1 mixture of diastereomeric hydroxylactams 543, which, on treatment with acid, give rise to the formation of the enantiomerically pure chiral /V-acylimini-um ions 6,... 

Reaction with chelating agents. Such reactions have been used primarily for partial dealumination of Y zeolites. In 1968, Kerr (8,21) reported the preparation of aluminum-deficient Y zeolites by extraction of aluminum from the framework with EDTA. Using this method, up to about 50 percent of the aluminum atoms was removed from the zeolite in the form of a water soluble chelate, without any appreciable loss in zeolite crystallinity. Later work (22) has shown that about 80 percent of framework aluminum can be removed with EDTA, while the zeolite maintains about 60 to 70 percent of its initial crystallinity. Beaumont and Barthomeuf (23-25) used acetylacetone and several amino-acid-derived chelating agents for the extraction of aluminum from Y zeolites. Dealumination of Y zeolites with tartaric acid has also been reported (26). A mechanism for the removal of framework aluminum by EDTA has been proposed by Kerr (8). It involves the hydrolysis of Si-O-Al bonds, similar to the scheme in Figure 1A, followed by formation of a soluble chelate between cationic, non-framework aluminum and EDTA. 

Amines are particularly prone to reaction with excipients and salt counterions, as shown in Figure 45 for tartaric acid. The potential for a reaction with magnesium stearate or stearic acid is particularly of concern with an API containing a primary amine. In the case of norfloxacin, formation of a stearoyl derivative was observed in tablets containing magnesium stearate after prolonged storage at 60°C (Fig. 46) (81). 

Recently, complex formation reactions of (A,A)-tartaric acid (TA) and its 0,0 -dibenzoyl derivative (DBTA) with a series of chiral alcohols (26, 27, 8 and 28, Scheme 11) were investigated in our laboratory using Toda s suspension method. [35] As an example, resolution of 28 is outlined in Scheme 12. 

Toda, F., and Tanaka, K. Efficient optical resolution of 2,2 -dihydroxy-binaphtyl and related compounds by complex formation with novel chiral host compounds derived from tartaric acid, J. Org. Chem. 1988, 53, 3607-3609. 

TADDOL is one of the oldest, and most extraordinarily versatile, chiral auxiliaries (Scheme 1.8). The initial design of TADDOL was driven by practical considerations, mainly because it is derived from tartaric acid - the least-expensive chiral starting material with twofold symmetry available from natural sources. The two hydroxyl functions of the genuine molecule can act as a double hydrogen-bond donor, allowing the formation of bidentate complexes. Moreover, these functions can be easily substituted, giving access to a variety of derivatives. 

Numerous examples of stereospecific reactions in the gas phase are reported in the mass spectrometric literature [1,2]. Many if not most of them, however, deal with relatively rigid systems, e.g., 1, or polyfunctional molecules such as derivatives of tartaric acid [6] the latter gave rise to the first chirality effect observed in mass spectrometry [7]. For stereogenic centers linked by flexible alkyl chains, however, diastereoisomeric differentiation in ion fragmentation is often poor. Two epimers of the aminoalkanol 2, for example, show quite small differences in their mass spectra whereas these differences increase if the two centers are linked by cyclization upon formation of 3 as indicated in Scheme 2 with the epimeric center being marked by an asterisk [8]. 

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