The chemistry of .alpha.-silyl carbonyl compounds. 11. Reaction of .alpha.-silyl esters with grignard reagents: a synthesis of .beta.-keto silanes and ketones. Preparation of the douglas fir tussock moth pheromone

Abstract

a-Cyclohexylidene-7-butyroIactone. This material was prepared in 60% yield and showed the following properties: IR (neat) 1740 and 1655 cm"1;

Regio‐ and Diasteroselective C‐Silylation of Enolate Enabled by a β‐Boronyl Group

“…In some cases, otherwise, a mixture of O ‐ and C‐silylated products are formed. [ 4 ] To overcome the inherent limitations, alternative approaches have been devised (Scheme 1b). Thus, C ‐silylation of hydrazones was possible and after deprotection, the desired C ‐silylated carbonyl compounds could be prepared (Scheme 1b, route A).…”

Regioselective Arene and Heteroarene Functionalization: N-Alkenoxypyridinium Salts as Electrophilic Alkylating Agents for the Synthesis of α-Aryl/α-Heteroaryl Ketones

“…1-Phenylundecan-2-one (5a). 21 Colorless oil (236 mg, 63%); 1 H NMR (400 MHz, CDCl 3 ) δ 7. 2H),1H),2H),3.67 (s,2H),2.42 (t,J = 7.3 Hz,2H),2H),12H), 0.86 (t, J = 6.9 Hz, 3H); 13 C NMR (100 MHz, CDCl 3 ) δ 208.7, 134.4, 129.4, 128.7, 126.9, 50.1, 42.0, 31.8, 29.4, 29.4, 29.2, 29.1, 23.7, 22.7, 14.1;IR (cm −1 ) 2917IR (cm −1 ) , 2849IR (cm −1 ) , 1708IR (cm −1 ) , 1601IR (cm −1 ) ,1464HRMS (ESI) .1905.…”

Cyclizations versus rearrangements in the reactions of some epoxyolefins with Lewis acids†

“…These compounds could have been formed via two different reactions of the presumed silylketone 60: a direct protiodesilylation or, alternatively, by C-O rearrangement of the α-TMS group to give the corresponding silylenol ether, which after hydrolytic work-up or during chromatography resulted in methylketone 61. 71 The other reaction, the intramolecular acetalization leading to the bicyclic acetals 63 and 64, took place on silica gel and on dry neutral alumina. The isolation and purification of 61 therefore had to be conducted on wet alumina (10% water).…”