Contents. No.97. New Z-selective Horner-Emmons Reagents Novel tert-butyldimethylsilylation... 6 Bifunctional Bithiophene TOKYO KASEI KOGYO CO.,LTD.

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1 998 o.97 TKY KAEI KGY C.,LTD. Tel: Fax: Contents for ynthesis Protected ydroxylamine... 2 Catalytic xidation Burgess Burgess eagent... 3 indered Acetylenes... 4 for ynthesis of 3-ubstituted Pyrroles Useful Lewis Acid Catalyst... 5 ew Z-selective orner-emmons eagents ovel tert-butyldimethylsilylation... 6 Bifunctional Bithiophene

2 / Protected ydroxylamine T725 -(2-Trimethylsilylethyl)hydroxylamine ydrochloride 5g 9,800 g 6,650 Boc C 2 Me 2 C 2 C 2 ime 3. Cl MeC 2, reflux, h, ac 3 C 2 Me Boc ime 3 several steps C 2 Me C 2 Me BF 3 Et 2 ) -Protected hydroxylamine T. enmi, T. akamoto, Y. Kikugawa, rg. Prep. Proced. Int., 26, (994) 2) ynthesis of nannochelin A T. akamoto,. Li, Y. Kikugawa, J. rg. Chem., 6, 8496 (996) / Catalytic xidation D2542 Di-µ-hydroxo-bis[(,,','-tetramethylethylenediamine)copper(II)] Chloride 5g 4,500 Me Me Me 2 Me Cu Cu 2Cl - Me Me Me Me 2C C (cat.), 2 C C C C acetone ) ) xidative coupling of acetylenes A.. ay, J. rg. Chem., 27, 3320 (962) 2) ynthesis of Binaphthol Derivatives M. oji, M. akajima, K. Koga, Tetrahedron Lett., 35, 7983 (994) 3) eview 32, 085 (996) 2

3 Burgess / Burgess eagent M279 (Methoxycarbonylsulfamoyl)triethylammonium ydroxide, Inner alt (Burgess eagent) g 8,400 Et 3 - Me, 2 - Me 95 Et Me ) C 3 C 2 2), Et 3 TF, reflux Y. quant. Boc C 2 C 2 Cl 2, 25 Boc C Y.9% 3) E. M. Burgess 2 3 β ) Thermal reactions of alkyl -carbomethoxysulfamate esters E. M. Burgess,.. Penton, Jr., E. A. Taylor, J. rg. Chem., 38, 26 (973) 2) Conversion of secondary and tertiary alcohols to olefins. McCague, J. Chem. oc., Perkin Trans., 987, 0 J. P. Marino, M. P. Ferro, J. rg. Chem., 46, 92 (98) D. J. Goldsmith,.. Kezar, Tetrahedron Lett., 2, 3543 (980) P. Crabbé, C. León, J. rg. Chem., 35, 2594 (970) 3) An efficient chemoselective synthesis of nitriles from primary amides D. A. Claremon, B. T. illips, Tetrahedron Lett., 29, 255 (988) 4) A new route to tributyltin isocyanate M. atier, D. Khatmi, J. G. Duboudin, D. T. Minh, ynth. Commun., 9, 929 (989) 5) Cyclodehydration of amino acid residues P. Wipf, C. P. Miller, J. rg. Chem., 58, 575 (993) idem, Tetrahedron Lett., 33, 907 (992) P. Wipf, C. P. Miller,. Venkatraman, P. C. Fritch, ibid., 36, 6395 (995) P. Wipf, P. C. Fritch, J. Am. Chem. oc., 8, 2358 (996) 3

4 / indered Acetylenes T690 -(Triisopropylsilyl)propyne 5ml,000 T683 Triisopropylsilylacetylene 2 5ml 0,000 ) MeC Ci 3 9-BB 9-BB= 9-Borabicyclo[3.3.]nonane C Me B C i 3 B C C Me i 3 B C C B 3 i Me 3 α 3 β 4 = Me 54% 0% 23% i Pr 0% 00% 0% 2 α (3α) (4) β (3β) 4 2 ) The hydroboration of silylacetylenes J. A. oderquist, J. C. Colberg, L. D. Valle, J. Am. Chem. oc.,, 4873 (989) 2) Useful synthetic reagents derived from -triisopropylsilylpropyne E. J. Corey, C. ücker, Tetrahedron Lett., 23, 79 (982) 3) ilicon-directed azarov reactions T. K. Jones,. E. Denmark, elv. Chim. Acta, 66, 2397 (983) 4) Towards the synthesis of tetraethynylallene T. Lange, J.-D. van Loon,.. Tykwinski, M. chreiber, F. Diederich, ynthesis, 996, 537 / for ynthesis of 3-ubstituted Pyrroles B899 3-Bromo--(triisopropylsilyl)pyrrole g 8,250 Br E E i) t BuLi, TF/-78 Bu 4 F iipr 3 ii) EX iipr 3 when EX = C 3 I Y.92% = n C 8 37 I Y.88% =TMCl Y.87% 2 2 For synthesis of 3-substituted pyrroles J. M. Muchowski, D.. olas, Tetrahedron Lett., 24, 3455 (983) B. L. Bray, P.. Mathies,. aef, D.. olas, T. T. Tidwell, D.. Artis, J. M. Muchowski, J. rg. Chem., 55, 637 (990) 4

5 / Useful Lewis Acid Catalyst T658 Titanocene Bis(trifluoromethanesulfonate) 00mg 5,750 a) TM Tf Ti Tf (0.5mol%) Me 2,, 35min. TM Y.90% TM Me Me Me (0.5mol%) Me 2, 25, <5min. Me Me Y.90% b) TM=Trimethylsilyl group T. K. ollis ) omogeneous catalyst a) for Mukaiyama cross-aldol reaction T. K. ollis,. P. obinson, B. Bosnich, Tetrahedron Lett., 33, 6423 (992) b) for akurai reaction T. K. ollis,. P. obinson, J. Whelan, B. Bosnich, Tetrahedron Lett., 34, 4309 (993) c) for Mukaiyama aldol and akurai allylation reactions T. K. ollis, B. Bosnich, J. Am. Chem. oc., 7, 4570 (995) d) for Diels-Alder reaction T. K. ollis,. P. obinson, B. Bosnich, rganometallics,, 2745 (992) / ew Z-selective orner-emmons eagents D2547 Diphenylphosphonoacetic Acid Ethyl Ester g 6,800 D2548 Di-o-tolylphosphonoacetic Acid Ethyl Ester 2 g 3,300 C Ar P C 2 C 2 Et Ar or 2 TF, -78, a (or Triton B) C 2 Et Ar= = Y. 98% (Z : E = 93 : 7) = n C 7 5 Y. 00% (Z : E = 90 :0) Ar= o-tolyl 2 = Y. 00% (Z : E = 96 : 4) = n C 7 5 Y. 97% (Z : E = 94 : 6) 2 Triton B Z-α,β- ) ighly selective synthesis of Z-unsaturated esters a) K. Ando, Tetrahedron Lett., 36, 405 (995) b) idem, J. rg. Chem., 62, 934 (997) c) 5

6 / ovel tert-butyldimethylsilylation B906,-Bis(tert-butyldimethylsilyl)acetamide 5g 8,700 TBDM C 3 C TBDM (0.6eq.), TBAF (0.03eq.) MP, r.t., 0.5h TBDM Y.95% (.2eq.), TBAF (0.05eq.) MP, r.t., 6h TBDM Y.97% (0.6eq.), TBAF (0.03eq.) C 2 Cl 2, r.t., 24h TBDM TBDM=tert-Butyldimethylsilyl group TBAF= Tetrabutylammonium Fluoride MP= -Methylpyrrolidinone Y.96% D. A. Johnson tert- Efficient method for the tert-butyldimethylsilylation of alcohols D. A. Johnson, L. M. Taubner, Tetrahedron Lett., 37, 605 (996) / Bifunctional Bithiophene B874 5-Bromo-2,2'-bithiophene-5'-carboxaldehyde 5g 8,400 g 6,50 ) icl 2, Zn, 3 P Br C DMF, reflux, 6h C C Y.78% 2 2 ) A convenient synthesis of functional group end-capped thiophene oligomers Y. Wei, B. Wang, W. Wang, J. Tian, Tetrahedron Lett., 36, 665 (995) 2) ynthesis of naturally occurring bithiophenes M. D Auria, A. De Mico, F. D nofrio, G. Piancatelli, J. rg. Chem., 52, 5243 (987) 3) Facile synthesis of α-polythienyls via,4-diketones T.-m.. Luo, E. LeGoff, J. Chin. Chem. oc., 39, 325 (992) 6