{"product_id":"small-ring-compounds-in-organic-synthesis-vi-von-armin-de-meijere-hrsg","title":"Small Ring Compounds in Organic Synthesis VI","description":"\u003cp\u003eSince the pioneering work by Sarel and co-workers on the iron carbonyl p- moted transformation of vinylcyclopropanes and related compounds [1],a - riety of transition metal complexes have been examined to achieve effective - tivation of the vinylcyclopropane-cyclopentene rearrangement which usually requires pyrolytic conditions. These reactions have been applied to natural product synthesis in some cases and have already been reviewed in several - cellent articles [2¿4]. Contrary to the well-established chemistry of the vinylcyclopropanes, the corresponding reactions of alkynyl- and propadienylcyclopropanes have not, until recently,received much attention.We present here a summary of the recent efforts towards the development of transition metal promoted transformation of these molecules with a brief survey of the corresponding thermal reactions. 2 Rearrangement of Alkynylcyclopropanols Unlike the well-known chemistry of the vinylcyclopropane-cyclopentene - arrangement, there is no general method for the rearrangement of alkyn- cyclopropane to cyclopentene derivatives.One specific example is the pyrolysis of 1-ethynyl-2-methylcyclopropane to methylenecyclopentene and other c- pounds [5].At 530°C, 1-ethynyl-2-methylcyclopropane (1) undergoes a [1,- hydrogen shift to give hexa-1,2,5-triene ( 2),which further isomerizes to met- lenecyclopentenes 3 and 4 in 38 and 29% yield,respectively (Scheme 1).\u003c\/p\u003e\u003cdiv class=\"aw-variant-hidden-subtitle-div\" id=\"aw-variant-subtitle-9783662156483\"\u003e\u003ch3\u003e\u003c\/h3\u003e\u003c\/div\u003e","brand":"Libri","offers":[{"title":"Softcover - 9783662156483","offer_id":39442539544669,"sku":"9783662156483","price":106.99,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0940\/0622\/files\/112e1a06-6f7d-4a4f-b224-7d99f620fe8e.jpg?v=1745993737","url":"https:\/\/shop.autorenwelt.de\/en\/products\/small-ring-compounds-in-organic-synthesis-vi-von-armin-de-meijere-hrsg","provider":"Autorenwelt Shop","version":"1.0","type":"link"}