Heteroatom Chemistry Volume 17, Number 5, 2006 Aryloxy Tetrazoles with Axial Chirality: Synthesis and Partial Resolution of 5-(1-(2-Methoxynaphthalen-1- yl)naphthalen-2-yloxy)-1H -tetrazole Hossein A. Dabbagh, Alireza Najafi Chermahini, and Abbas Teimouri Department of Chemistry, Isfahan University of Technology, 8415483111, Isfahan, Iran Received 25 July 2005; revised 29 November 2005 ABSTRACT: 5-(1-(2-Methoxynaphthalen-1-yl)naph- thalen-2-yloxy)-1H-tetrazole as the first aryloxy tetrazole with axial chirality was synthesized. Partial resolution was achieved using (S)-proline and methyl- benzylamine as the resolving agents. Best results were obtained using methylbenzylamine with 75–85% ee. C  2006 Wiley Periodicals, Inc. Heteroatom Chem 17:416–419, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20241 INTRODUCTION Despite the scarcity of tetrazoles compounds in nat- ural systems, the chemistry of this heterocycles has gained an increasing attention since the early 1980s [1]. This interest stems from the ability of tetrazoles to mimic the carboxylic acid group, which has moti- vated the incorporation of tetrazoles in biologically active molecules [2]. Another research area of major interest is the therapeutic application of tertrazoles which has been included in pharmacologically active compounds with antihypertensive, antiallergic, and antibiotic activities [3]. Tetrazoles have found wide Correspondence to: H. A. Dabbagh; e-mail: dabbagh@cc.iut.ac.ir. Contract grant sponsor: Isfahan University of Technology Research Council. Contract grant number: 84/500/9143. c  2006 Wiley Periodicals, Inc. application in agriculture biology and explosives [4]. Optically active BINOL and its relative com- pounds with axial chirality have wide application in asymmetric ligands [5,6], Michael addition [7], enan- tioselective hydrogenation [8], and chiral-reducing agents [9,10] and more [11–14]. Recently Kocovsky et al. reviewed application of nonsymmetrically binaphthyl compounds in enan- tioselective synthesis [15]. In the course of our research on the chemistry of tetrazoles [16–20], herein we report the first example of synthesis and partial resolution of aryloxy tetra- zoles with axial chirality. Chiral tetrazoles, besides their very important role in their own chemistry, are very important precursor to a wide range of func- tional groups such as amines, aziridines, azapenes, isoureas, and more [1–4,16–20]. EXPERIMENTAL Potassium carbonate and solvents were pur- chased from Merck, methyl iodide was purchased from Riedel-Dehaen, and optically active 1,1 ′ - binaphthalen-2,2 ′ -diol was purchased from Fluka. Racemic 1,1 ′ -binaphthalen-2,2 ′ -diol was synthesized by the method described in [21]. IR spectra were recorded on a Jasco FT/IR-680 Plus spectrome- ter. NMR spectra were recorded on a Bruker 500 ultrasheild NMR and CDCl 3 , and DMSO-d 6 was used as a solvent. Optical rotation measurements 416